1000 Sentences With "subunit" | Random Sentence Generator

By comparison, Shingrix is a non-live, subunit vaccine that works by introducing only an essential subunit of the actual microbe.

The alpha subunit is located on the outside surface of mast cell while the beta subunit is located within the cellular membrane itself.

A subunit known as the Joint Force Space Component command handles space.

AI is useful in accelerating the development of subunit and nucleic acid vaccines.

The new dictionary introduces "qapik," which means "a monetary subunit of the manat" in Azerbaijan.

NCT 127, of which Taeyong and Mark are staples of, is a subunit of the group.

Soleimani leads the Quds Force, a subunit of the Islamic Revolutionary Guard Corps (IRGC) responsible for Iran's extraterritorial operations.

Strong agonists for either subunit of the 5HT2A-mGlu2R heterocomplex suppress signaling through the partner subunit and inverse agonists for either subunit potentiate the signaling through the partner subunit.

LFA-1 is a heterodimeric glycoprotein with non-covalently linked subunits. LFA-1 has two subunits designated as the alpha subunit and beta subunit. The alpha subunit was named aL in 1983. The alpha subunit is designated CD11a; and the beta subunit, unique to leukocytes, is beta-2 or CD18.

The other transmembrane subunit is SDHC. The SDHC/SDHD dimer is connected to the SDHB electron transport subunit which, in turn, is connected to the SDHA subunit.

Farnesyltransferase has two subunits: a 48kDa alpha subunit and a 46kDa beta subunit. Both subunits are primarily composed of alpha helices. The α subunit is made of a double layer of paired alpha helices stacked in parallel, which wraps partly around the beta subunit like a blanket. The alpha helices of the β subunit form a barrel.

This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The beta subunit regulates, through assembly of alpha/beta heterodimers, the number of sodium pumps transported to the plasma membrane. The glycoprotein subunit of Na+/K+-ATPase is encoded by multiple genes. This gene encodes a beta 1 subunit.

Each PP1 enzyme contains both a catalytic subunit and at least one regulatory subunit. The catalytic subunit consists of a 30-kD single-domain protein that can form complexes with other regulatory subunits. The catalytic subunit is highly conserved among all eukaryotes, thus suggesting a common catalytic mechanism. The catalytic subunit can form complexes with various regulatory subunits.

Subunit alpha is the variable subunit, and beta is the catalytic chain. The structure of the beta subunit has been determined and found to fold around the FeS cluster.

The beta-3 subunit has very similar function to the human version of the subunit.

During protease Clp complex assembly, the ClpX subunits form a hexameric ring structure. According to the orientation of ClpX subunits within the ring structure, these subunits can be categorized into two classes: "loadable" subunit (L subunit) and "unloadable" subunit (U subunit). In L subunit, the large and small AAA+ domain form a cleft for nucleotide ATP or ADP binding. However, the large and small AAA+ domains in U subunit rotate ~ 80°, which prevents nucleotide binding.

As the alpha subunit of Mitochondrial- processing peptidase, PMPCA forms a heterodimer with the subunit PMPCB.

The β subunit regulates the kinetics and expression of the channel, along with the α2δ subunit.

Glutaconyl-CoA decarboxylase (EC 4.1.1.70; TC# 3.B.1.1.3) consists of four subunits: α (GcdA, 587 amino acyl residues (aas); catalytic subunit), β (GcdB, 375 aas; 9 TMSs; Na+-transporter subunit), γ (GcdC, 145 aas; biotin-carrier subunit) and δ (GcdD, 107 aas; 1 TMS; the GcdA anchor protein). The catalytic subunit of all four enzyme porters are biotin- containing multi-subunit enzymes.

Ribosomal particles are denoted according to their sedimentation coefficients in Svedberg units. The 60S subunit is the large subunit of eukaryotic 80S ribosomes. It is structurally and functionally related to the 50S subunit of 70S prokaryotic ribosomes. However, the 60S subunit is much larger than the prokaryotic 50S subunit and contains many additional protein segments, as well as ribosomal RNA expansion segments.

The B' subunit is similar in structure to the scaffold subunit and makes extensive interactions with the scaffold subunit, through a convex surface with eight HEAT repeats, and the catalytic subunit (Janssens & Goris, 2001). A concave, acidic region of the B' subunit is tilted towards the active site of the catalytic subunit in the holoenzyme (Janssens & Goris, 2001). The B subunit contains seven WD40 repeats, a β-hairpin handle and other secondary structures that form a β-propeller (Janssens & Goris, 2001). The β-propeller and β-hairpin handle interact with HEAT repeats three to seven and one to two on the scaffold subunit, respectively (Janssens & Goris, 2001).

This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The catalytic subunit of Na+/K+-ATPase is encoded by multiple genes. This gene encodes an alpha 1 subunit. Alternatively spliced transcript variants encoding different isoforms have been identified.

This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The catalytic subunit of Na+/K+ -ATPase is encoded by multiple genes. This gene encodes an alpha 4 subunit. Alternatively spliced transcript variants encoding different isoforms have been identified.

The fragment of 43 amino acids at peptide N-terminal is essential for proper protein folding and subsequent complex assembly. At the end-stage of complex assembly, the N-terminal fragment of beta5 subunit is cleaved, forming the mature beta2 subunit of 20S complex. During the basal assembly, and proteolytic processing is required to generate a mature subunit. This subunit is not present in the immunoproteasome and is replaced by catalytic subunit 2i (proteasome beta 10 subunit).

Acetylcholine receptor subunit epsilon is a protein that in humans is encoded by the CHRNE gene. Acetylcholine receptors at mature mammalian neuromuscular junctions are pentameric protein complexes composed of four subunits in the ratio of two alpha subunits to one beta, one epsilon, and one delta subunit. The achetylcholine receptor changes subunit composition shortly after birth when the epsilon subunit replaces the gamma subunit seen in embryonic receptors. Mutations in the epsilon subunit are associated with congenital myasthenic syndrome.

As the beta subunit of Mitochondrial- processing peptidase, PMPCB forms a heterodimer with the subunit Mitochondrial-processing peptidase subunit alpha. In addition, PMPCB has been shown to interact with PMPCA and Frataxin.

Protein phosphatase 1 regulatory subunit 12B is an enzyme that in humans is encoded by the PPP1R12B gene. Myosin light chain phosphatase (MLCP) consists of three subunits- catalytic subunit, large subunit/myosin binding subunit (MBS) and small subunit (sm-M20). This gene is a multi-functional gene which encodes both MBS and sm-M20. MLCP regulates myosins and the dephosphorylation is enhanced by the presence of MBS.

The fragment of 39 amino acids at peptide N-terminal is essential for proper protein folding and subsequent complex assembly. At the end-stage of complex assembly, the N-terminal fragment of beta2i subunit is cleaved, forming the mature beta2i subunit of 20S complex. During the basal assembly, and proteolytic processing is required to generate a mature subunit. The subunit beta5i only presents in the immunoproteasome and is replaced by subunit beta5(proteasome beta 5 subunit) in constitutive 20S proteasome complex.

The fragment of 72 amino acids at peptide N-terminal is essential for proper protein folding and subsequent complex assembly. At the end-stage of complex assembly, the N-terminal fragment of beta5 subunit is cleaved, forming the mature beta5i subunit of 20S complex. During the basal assembly, and proteolytic processing is required to generate a mature subunit. The subunit beta5i only presents in the immunoproteasome and is replaced by subunit beta5(proteasome beta 5 subunit) in constitutive 20S proteasome complex.

The fragment of 72 amino acids at peptide N-terminal is essential for proper protein folding and subsequent complex assembly. At the end-stage of complex assembly, the N-terminal fragment of beta5i subunit is cleaved, forming the mature beta5i subunit of 20S complex. During the basal assembly, and proteolytic processing is required to generate a mature subunit. The subunit beta5i only presents in the immunoproteasome and is replaced by subunit beta5(proteasome beta 5 subunit) in constitutive 20S proteasome complex.

The 116kDa subunit (or subunit a) and subunit I are found in the Vo or Ao complex of V- or A-ATPases, respectively. The 116kDa subunit is a transmembrane glycoprotein required for the assembly and proton transport activity of the ATPase complex. Several isoforms of the 116kDa subunit exist, providing a potential role in the differential targeting and regulation of the V-ATPase for specific organelles. The function of the 116-kDa subunit is not defined, but its predicted structure consists of 6–8 transmembranous sectors, suggesting that it may function similar to subunit a of FO.

Condensin complex subunit 3 also known as condensin subunit CAP-G (CAP-G) or non-SMC condensin I complex subunit G (NCAPG) is a protein that in humans is encoded by the NCAPG gene. CAP-G is a subunit of condensin I, a large protein complex involved in chromosome condensation.

Subunit 2 associates with pre-mRNA upstream of the branch site at the anchoring site. Subunit 2 also interacts directly with subunit 4 of the splicing factor 3b complex. Subunit 2 is a highly hydrophilic protein with a proline-rich N-terminus and a glutamate-rich stretch in the C-terminus.

The polypeptides composing the multi-subunit ACCs of prokaryotes and plants are encoded by distinct genes. In Escherichia coli, accA encodes the alpha subunit of the acetyl-CoA carboxylase, and accD encodes its beta subunit.

The catalytic subunit of Na+/K+-ATPase is encoded by multiple genes. This gene encodes an alpha 2 subunit.

The catalytic subunit of Na+/K+-ATPase is encoded by multiple genes. This gene encodes an alpha 3 subunit.

The eukaryotic small ribosomal subunit (40S) is the smaller subunit of the eukaryotic 80S ribosomes, with the other major component being the large ribosomal subunit (60S). The "40S" and "60S" names originate from the convention that ribosomal particles are denoted according to their sedimentation coefficients in Svedberg units. It is structurally and functionally related to the 30S subunit of 70S prokaryotic ribosomes. However, the 40S subunit is much larger than the prokaryotic 30S subunit and contains many additional protein segments, as well as rRNA expansion segments.

The gene ATP4BATP4B ATPase H+/K+ transporting beta subunit encodes the β subunit of the H+/K+ ATPase, which is an ~300-amino acid protein with a 36-amino acid N-terminal cytoplasmic domain, a single transmembrane domain, and a highly glycosylated extracellular domain. Structure of the hydrogen potassium ATPase. The α subunit is shown in pink; the β subunit is shown in blue. The H+/K+ ATPase β subunit stabilizes the H+/K+ ATPase α subunit and is required for function of the enzyme.

Atomic structure of the 30S Subunit from Thermus thermophilus. Proteins are shown in blue and the single RNA strand in orange. The prokaryotic small ribosomal subunit, or 30S subunit, is the smaller subunit of the 70S ribosome found in prokaryotes. It is a complex of the 16S ribosomal RNA (rRNA) and 19 proteins.

Proteasome subunit alpha 8 also known as proteasome subunit alpha type-7-like is a protein that in humans is encoded by the PSMA8 gene. Proteasome subunit alpha 8 is a component of the sperm specific proteasome.

The SDHC protein is one of the two transmembrane subunits of the four-subunit succinate dehydrogenase (Complex II) protein complex that resides in the inner mitochondrial membrane. The other transmembrane subunit is SDHD. The SDHC/SDHD dimer is connected to the SDHB electron transport subunit which, in turn, is connected to the SDHA subunit.

Atomic structure of the 50S Subunit from Haloarcula marismortui. Proteins are shown in blue and the two RNA strands in orange and yellow. The small patch of green in the center of the subunit is the active site. Atomic structure of the 50S large subunit of the ribosome, facing the 30S small ribosomal subunit.

However, its effects are limited to pentamers containing the δ-subunit rather than the γ-subunit. GABAA receptors containing the δ-subunit have been shown to be located exterior to the synapse and are involved with tonic inhibition rather than its γ-subunit counterpart, which is involved in phasic inhibition. The δ-subunit has been shown to be able to form the allosteric binding site which makes GABAA receptors containing the δ-subunit more sensitive to ethanol concentrations, even to moderate social ethanol consumption levels (30mM). While it has been shown by Santhakumar et al.

This gene encodes a constant regulatory subunit of protein phosphatase 2. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The constant regulatory subunit A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit.

Interleukin 13 receptor, alpha 1, also known as IL13RA1 and CD213A1 (cluster of differentiation 213A1), is a human gene. The protein encoded by this gene is a subunit of the interleukin 13 receptor. This subunit forms a receptor complex with IL4 receptor alpha, a subunit shared by IL13 and IL4 receptors. This subunit serves as a primary IL13-binding subunit of the IL13 receptor, and may also be a component of IL4 receptors.

Connecting the two subunits is a tunnel of sorts, which directs the ammonia from the small subunit to the large subunit.

The alpha Subunit of the Gs protein releases bound GDP and binds GTP. The alpha subunit-GTP complex dissociates from the beta and gamma dimer and interacts with adenylate cyclase. Binding of glucagon molecule activates many of the alpha subunit, which amplifies the hormonal signal. Then, the alpha subunit activates the adenylate cyclase, which converts ATP to cAMP.

Eukaryotic Initiation Factor 2 (eIF2) is a eukaryotic initiation factor. It is required for most forms of eukaryotic translation initiation. eIF2 mediates the binding of tRNAiMet to the ribosome in a GTP-dependent manner. eIF2 is a heterotrimer consisting of an alpha (also called subunit 1, EIF2S1), a beta (subunit 2, EIF2S2), and a gamma (subunit 3, EIF2S3) subunit.

PT is known to dissociate into two parts in the endoplasmic reticulum (ER): the enzymatically active A subunit (S1) and the cell-binding B subunit. The two subunits are separated by proteolic cleavage. The B subunit will undergo ubiquitin-dependent degradation by the 26S proteasome. However, the A subunit lacks lysine residues, which are essential for ubiquitin- dependent degradation.

Crystal structure of the NatA complex (Naa10 and Naa15) from Schizosaccharomyces pombe. The green chains represent the auxiliary subunit Naa15 and the cyan chains the catalytic subunit Naa10. (PDB ID: 4KVM) NatA is composed of two subunits, the catalytic subunit Naa10 and the auxiliary subunit Naa15. NatA subunits are more complex in higher eukaryotes than in lower eukaryotes.

The large subunit contains a N-terminal 4Fe–4S cluster, split out in some archaea as PriX/PriCT. The large subunit is implicated in improving the activity and specificity of the small subunit. For example, removing the part corresponding to the large subunit in a fusion protein PolpTN2 results in a slower enzyme with reverse transcriptase activity.

Phosphoinositide 3-kinase regulatory subunit 4, also known as PI3-kinase regulatory subunit 4 or PI3-kinase p150 subunit or phosphoinositide 3-kinase adaptor protein, or VPS15 is an enzyme that in humans is encoded by the PIK3R4 gene.

Serine/threonine-protein phosphatase 2A regulatory subunit B subunit gamma is an enzyme that in humans is encoded by the PPP2R3C gene.

Serine/threonine-protein phosphatase 2A regulatory subunit B subunit beta is an enzyme that in humans is encoded by the PPP2R3B gene.

Interleukin 15 receptor, alpha subunit is a subunit of the interleukin 15 receptor that in humans is encoded by the IL15RA gene.

Barbiturates' precise action sites have not yet been defined. The second and third transmembrane domains of the β subunit appear to be critical; binding may involve a pocket formed by β-subunit methionine 286 as well as α-subunit methionine 236.

The gene PSMB5 encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit in the proteasome. This catalytic subunit is not present in the immunoproteasome and is replaced by catalytic subunit beta5i (proteasome beta 8 subunit). The gene has 5 exons and locates at chromosome band 14q11.2. The human protein proteasome subunit beta type-5 is 22 kDa in size and composed of 204 amino acids.

Its interaction with the catalytic subunit occurs mainly with two loops between β strands. The residues in these two loops are mostly conserved and are thought to stabilize the 4Fe-4S cluster in the catalytic subunit. Structurally, the α subunit is very similar to the PsaE protein, a subunit of Photosystem I, though the similarity is not seen in their sequences or functions. The catalytic β subunit has a general α-helical structure with an [4Fe-4S center].

Ribonuclease H2 subunit A, also known as RNase H2 subunit A, is an enzyme that in humans is encoded by the RNASEH2A gene.

Salt bridges and hydrogen bonds, dashed lines; labels of residues from the yellow subunit, red; labels of residues from the cyan subunit, blue.

ZHD provides further contacts with the 60S subunit and connects to a subunit-spanning medium domain (MD), the "neck" of RAC. The four-helix-bundle RAC head domain is located at the C-terminus and binds the small (40S) subunit. The J domain-Ssz1p complex, located over the peptide exit tunnel of the large ribosomal subunit, helps the nascent peptide fold.

The alpha subunit polypeptide is encoded by the HEXA gene while the beta subunit is encoded by the HEXB gene. Gene mutations in the gene encoding the beta subunit (HEXB) often result in Sandhoff disease; whereas, mutations in the gene encoding the alpha subunit (HEXA, this gene) decrease the hydrolysis of GM2 gangliosides, which is the main cause of Tay–Sachs disease.

Furthermore, the beta A subunit forms a homodimer, activin A, and also joins with a beta B subunit to form a heterodimer, activin AB, both of which stimulate FSH secretion. Finally, it has been shown that the beta A subunit mRNA is identical to the erythroid differentiation factor subunit mRNA and that only one gene for this mRNA exists in the human genome.

ATP synthase subunit delta, mitochondrial, also known as ATP synthase F1 subunit delta or F-ATPase delta subunit is an enzyme that in humans is encoded by the ATP5F1D (formerly ATP5D) gene. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation.

Signal recognition particle receptor subunit beta is a protein that in humans is encoded by the SRPRB gene. The protein encoded by this gene has similarity to mouse protein which is a subunit of the signal recognition particle receptor (SR). This subunit is a transmembrane GTPase belonging to the GTPase superfamily. It anchors alpha subunit, a peripheral membrane GTPase, to the ER membrane.

Luteinizing hormone subunit beta also known as lutropin subunit beta or LHβ is a polypeptide that in association with an alpha subunit common to all gonadotropin hormones forms the reproductive signaling molecule luteinizing hormone. In humans it is encoded by the LHB gene.

Mitochondrial import inner membrane translocase subunit TIM16 also known as presequence translocated-associated motor subunit PAM16, mitochondria- associated granulocyte macrophage CSF-signaling molecule, or presequence translocated-associated motor subunit PAM16 is a protein that in humans is encoded by the PAM16 gene.

Guselkumab targets the IL-23 subunit alpha (p19 subunit) preventing it from binding to cell receptors that would otherwise be activated by its presence.

Ribbon diagram of cholera toxin. From .Ribbon diagram of pertussis toxin. S1 is the A subunit, and S2-S5 make up the B subunit.

At the end-stage of complex assembly, the N-terminal fragment of beta1 subunit is cleaved, forming the mature beta1 subunit of 20S complex.

The MOCS2 gene contains 7 exons. Exons 1 to 3 encode MOCS2A (the small subunit), and exons 3 to 7 encode MOCS2B (large subunit).

Binding at the α1β3γ2 GABAA receptor. Alprazolam with red space-filling carbon atoms. γ2 receptor subunit in mint green. The α1' subunit is hidden.

Ribonucleoside-diphosphate reductase subunit M2, also known as ribonucleotide reductase small subunit, is an enzyme that in humans is encoded by the RRM2 gene.

The protein encoded by this gene is an interleukin 3 specific subunit of a heterodimeric cytokine receptor. The receptor is composed of a ligand specific alpha subunit and a signal transducing beta subunit shared by the receptors for interleukin 3 (IL3), colony stimulating factor 2 (CSF2/GM-CSF), and interleukin 5 (IL5). The binding of this protein to IL3 depends on the beta subunit. The beta subunit is activated by the ligand binding, and is required for the biological activities of IL3.

The protein encoded by this gene is an interleukin 5 specific subunit of a heterodimeric cytokine receptor. The receptor is composed of a ligand specific alpha subunit and a signal transducing beta subunit shared by the receptors for interleukin 3 (IL3), colony stimulating factor 2 (CSF2/GM-CSF), and interleukin 5 (IL5). The binding of this protein to IL5 depends on the beta subunit. The beta subunit is activated by the ligand binding, and is required for the biological activities of IL5.

Each subunit is encoded by its own "gene" (a coding locus). The DQ α subunit is encoded by the HLA-DQA1 gene and the DQ β subunit is encoded by the HLA-DQB1 gene. Both loci are variable in the human population (see regional evolution).

F-actin-capping protein subunit alpha-1 is a protein that in humans is encoded by the CAPZA1 gene. CAPZA1 is a member of the F-actin capping protein alpha subunit family. This gene encodes the alpha subunit of the barbed-end actin binding protein.

PP2A subunit B isoform delta also known as serine/threonine-protein phosphatase 2A 55 kDa regulatory subunit B delta isoform is a protein that in humans is encoded by the PPP2R2D gene. It is a regulatory subunit of the heterotrimeric protein phosphatase 2 enzyme.

COP9 signalosome complex subunit 2 is a protein that in humans is encoded by the COPS2 gene. It encodes a subunit of the COP9 signalosome.

The alpha subunit of PCC contains the biotin carboxylase (BC) and biotin carboxyl carrier protein (BCCP) domains. A domain known as the BT domain is also located on the alpha subunit and is essential for interactions with the beta subunit. The 8-stranded anti-parallel beta barrel fold of this domain is particularly interesting. The beta subunit contains the carboxyltransferase (CT) activity. Figure 1.(a).

A dodecameric protein has a quaternary structure consisting of 12 protein subunits in a complex. Dodecameric complexes can have a number of subunit 'topologies', but typically only a few of the theoretically possible subunit arrangements are observed in protein structures. A dodecamer (protein) is a protein complex with 12 protein subunits. A common subunit arrangement involves a tetrahedral distribution of subunit trimers (or 3-4-point symmetry).

Rod cGMP-specific 3',5'-cyclic phosphodiesterase subunit beta is the beta subunit of the protein complex PDE6 that is encoded by the PDE6B gene. PDE6 is crucial in transmission and amplification of visual signal. The existence of this beta subunit is essential for normal PDE6 functioning. Mutations in this subunit are responsible for retinal degeneration such as retinitis pigmentosa or congenital stationary night blindness.

In Cav1.3 channels, the α1 subunit is α1D. This subunit differentiates Cav1.3 channels from other members of the Cav1 family, such as the predominant and better-studied Cav1.2, which has an α1C subunit. The significance of the α1 subunit also means that it is the primary target for calcium-channel blockers such as dihydropyridines. The remaining β, α2δ and γ subunits have auxiliary functions.

This dimerization is essential to create the active site; a p12 subunit is liberated and it is subsequently processed to the small p10 subunit. The two molecules of procapase-8 are associated with these p10 subunits creating an active protease-8 cell death. When two procaspase-8 are recruited to the DISC, their caspase domains undergo conformational changes with the consequent liberation of P12 subunit which is processed to the small P10 catalytic subunit. The intermediate capspase-8 breaks in the region between DED and P18 subunit.

Katanin p60 ATPase-containing subunit A1 is an enzyme that in humans is encoded by the KATNA1 gene. Microtubules, polymers of alpha and beta tubulin subunits, form the mitotic spindle of a dividing cell and help to organize membranous organelles during interphase. Katanin is a heterodimer that consists of a 60 kDa ATPase (p60 subunit A 1) and an 80 kDa accessory protein (p80 subunit B 1). The p60 subunit acts to sever and disassemble microtubules, while the p80 subunit targets the enzyme to the centrosome.

Katanin p80 WD40-containing subunit B1 is a protein that in humans is encoded by the KATNB1 gene. Microtubules, polymers of alpha and beta tubulin subunits, form the mitotic spindle of a dividing cell and help to organize membranous organelles during interphase. Katanin is a heterodimer that consists of a 60 kDa ATPase (p60 subunit A 1) and an 80 kDa accessory protein (p80 subunit B 1). The p60 subunit acts to sever and disassemble microtubules, while the p80 subunit targets the enzyme to the centrosome.

Calcium-activated potassium channel subunit beta-3 is a protein that in humans is encoded by the KCNMB3 gene. MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which may partially inactivate or slightly decrease the activation time of MaxiK alpha subunit currents.

In each subunit, when an input is received, a signal is sent to the other subunit. At the same time, the signal is delayed in time within the subunit, and after the temporal filter, is then multiplied by the signal received from the other subunit. Thus, within each subunit, the two brightness values, one received directly from its receptor with a time delay and the other received from the adjacent receptor, are multiplied. The multiplied values from the two subunits are then subtracted to produce an output.

Serine/threonine-protein phosphatase 2A regulatory subunit B subunit alpha is an enzyme that in humans is encoded by the PPP2R3A gene. Protein phosphatase 2 (formerly named type 2A) is one of the four major Ser/Thr phosphatases and is implicated in the negative control of cell growth and division. Protein phosphatase 2 holoenzymes are heterotrimeric proteins composed of a structural subunit A, a catalytic subunit C, and a regulatory subunit B. The regulatory subunit is encoded by a diverse set of genes that have been grouped into the B/PR55, B'/PR61, and B/PR72 families. These different regulatory subunits confer distinct enzymatic specificities and intracellular localizations to the holozenzyme.

Calcineurin subunit B type 1 also known as protein phosphatase 2B regulatory subunit 1 is a protein that in humans is encoded by the PPP3R1 gene.

Condensin-2 complex subunit D3 (CAP-D3) also known as non-SMC condensin II complex subunit D3 (NCAPD3) is a protein that in humans is encoded by the NCAPD3 gene. CAP-D3 is a subunit of condensin II, a large protein complex involved in chromosome condensation.

The 70 S ribosome from bacteria has a sedimentation coefficient of 70 svedberg, although it is composed of a 50 S subunit and a 30 S subunit.

DNA polymerase epsilon catalytic subunit is an enzyme that in humans is encoded by the POLE gene. It is the central catalytic subunit of DNA polymerase epsilon.

In this way, each subunit contributes to the binding site on the neighboring subunit, and so the tetramer can also be considered a dimer of functional dimers.

Phosphatidylinositol 3-kinase catalytic subunit type 3 is an enzyme subunit that in humans is encoded by the PIK3C3 gene. It's a class III phosphoinositide 3-kinase.

ATP synthase delta subunit is a subunit of bacterial and chloroplast F-ATPase/synthase. It is known as OSCP (oligomycin sensitivity conferral protein) in mitochondrial ATPase (note that in mitochondria there is a different delta subunit, ATP synthase delta/epsilon subunit). The OSCP/delta subunit appears to be part of the peripheral stalk that holds the F1 complex alpha3beta3 catalytic core stationary against the torque of the rotating central stalk, and links subunit A of the FO complex with the F1 complex. In mitochondria, the peripheral stalk consists of OSCP, as well as FO components F6, B and D. In bacteria and chloroplasts the peripheral stalks have different subunit compositions: delta and two copies of FO component B (bacteria), or delta and FO components B and B' (chloroplasts).

Two distinctive ubiquinone binding sites can be recognized on mammalian SDH – matrix-proximal QP and matrix-distal QD. Ubiquinone binding site Qp, which shows higher affinity to ubiquinone, is located in a gap composed of SdhB, SdhC, and SdhD. Ubiquinone is stabilized by the side chains of His207 of subunit B, Ser27 and Arg31 of subunit C, and Tyr83 of subunit D. The quinone ring is surrounded by Ile28 of subunit C and Pro160 of subunit B. These residues, along with Il209, Trp163, and Trp164 of subunit B, and Ser27 (C atom) of subunit C, form the hydrophobic environment of the quinone-binding pocket Qp. In contrast, ubiquinone binding site QD, which lies closer to inter-membrane space, is composed of SdhD only and has lower affinity to ubiquinone.

MT-ATP8 (or ATP8) is a mitochondrial gene with the full name 'mitochondrially encoded ATP synthase membrane subunit 8' that encodes a subunit of mitochondrial ATP synthase, ATP synthase Fo subunit 8 (or subunit A6L). This subunit belongs to the Fo complex of the large, transmembrane F-type ATP synthase. This enzyme, which is also known as complex V, is responsible for the final step of oxidative phosphorylation in the electron transport chain. Specifically, one segment of ATP synthase allows positively charged ions, called protons, to flow across a specialized membrane inside mitochondria.

DNA-directed RNA polymerases I, II, and III subunit RPABC1 is a protein that in humans is encoded by the POLR2E gene. This gene encodes the fifth largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. This subunit is shared by the other two DNA- directed RNA polymerases and is present in two-fold molar excess over the other polymerase subunits. An interaction between this subunit and a hepatitis virus transactivating protein has been demonstrated, suggesting that interaction between transcriptional activators and the polymerase can occur through this subunit.

This gene encodes one of three GA-binding protein transcription factor subunits which functions as a DNA-binding subunit. Since this subunit shares identity with a subunit encoding the nuclear respiratory factor 2 gene, it is likely involved in activation of cytochrome oxidase expression and nuclear control of mitochondrial function. This subunit also shares identity with a subunit constituting the transcription factor E4TF1, responsible for expression of the adenovirus E4 gene. Because of its chromosomal localization and ability to form heterodimers with other polypeptides, this gene may play a role in the Down Syndrome phenotype.

Splicing factor 3A subunit 3 is a protein that in humans is encoded by the SF3A3 gene. This gene encodes subunit 3 of the splicing factor 3a protein complex. The splicing factor 3a heterotrimer includes subunits 1, 2 and 3 and is necessary for the in vitro conversion of 15S U2 snRNP into an active 17S particle that performs pre-mRNA splicing. Subunit 3 interacts with subunit 1 through its amino-terminus while the zinc finger domain of subunit 3 plays a role in its binding to the 15S U2 snRNP.

This gene encodes subunit 2 of the splicing factor 3a protein complex. The splicing factor 3a heterotrimer includes subunits 1, 2 and 3 and is necessary for the in vitro conversion of 15S U2 snRNP into an active 17S particle that performs pre-mRNA splicing. Subunit 2 interacts with subunit 1 through its amino-terminus while the single zinc finger domain of subunit 2 plays a role in its binding to the 15S U2 snRNP. Subunit 2 may also function independently of its RNA splicing function as a microtubule-binding protein.

This gene encodes the phosphatase 2A catalytic subunit. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. This gene encodes an alpha isoform of the catalytic subunit.

This gene encodes the phosphatase 2A catalytic subunit. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. This gene encodes a beta isoform of the catalytic subunit.

In response to receptor activation, the α subunit releases bound guanosine diphosphate (GDP), which is displaced by guanosine triphosphate (GTP), thus activating the α subunit, which then dissociates from the β and γ subunits. The activated α subunit can further affect intracellular signaling proteins or target functional proteins directly.

Cytochrome c oxidase subunit 5B, mitochondrial is an enzyme in humans that is a subunit of the cytochrome c oxidase complex, also known as Complex IV, the last enzyme in the mitochondrial electron transport chain. In humans, cytochrome c oxidase subunit 5B is encoded by the COX5B gene.

Since the usher can only translocate pilus subunits and not chaperone/subunit complexes, and the fact that the chaperone can't be energetically out-competed by another subunit (due to lack of P5) this terminating subunit anchors the pilus to the outer membrane and stop any further pilus growth.

CCR4-NOT transcription complex subunit 11 is a protein that in humans is encoded by the CNOT11 gene. It is a subunit of the CCR4-Not deadenylase complex.

CCR4-NOT transcription complex subunit 10 is a protein that in humans is encoded by the CNOT10 gene. It is a subunit of the CCR4-Not deadenylase complex.

CCR4-NOT transcription complex subunit 3 is a protein that in humans is encoded by the CNOT3 gene. It is a subunit of the CCR4-Not deadenylase complex.

CCR4-NOT transcription complex subunit 8 is a protein that in humans is encoded by the CNOT8 gene. It is a subunit of the CCR4-Not deadenylase complex.

CCR4-NOT transcription complex subunit 2 is a protein that in humans is encoded by the CNOT2 gene. It is a subunit of the CCR4-Not deadenylase complex.

CCR4-NOT transcription complex subunit 7 is a protein that in humans is encoded by the CNOT7 gene. It is a subunit of the CCR4-Not deadenylase complex.

The ε subunit is stabilized by the θ subunit within the complete polymerase complex. The gene encodes two functional domains: the N-terminus of the gene product binds the θ subunit and carries out the exonuclease function and the C-terminus binds the α subunit responsible for polymerase activity. A Q-linker peptide of 22 residues has been identified that links the α subunit to the ε subunit, conferring flexibility that sets the α:ε complex apart from other more restricted multi-domain proofreading polymerases. There is interaction between the missense suppressor glycine tRNA encoded by the mutA gene that is correlated to significantly increased mutation rate in cells that express the gene.

Some proteobacterial assemblies require a third subunit () to bind heme d; others do not. The high-resolution structure heterotrimeric Cytochromes bd from Geobacillus species has been determined (). The third subunit does not share sequence homology with the third subunit proteobacteria, but does come into the assemblies at a similar position.

Condensin-2 complex subunit H2, also known as chromosome-associated protein H2 (CAP-H2) or non-SMC condensin II complex subunit H2 (NCAPH2), is a protein that in humans is encoded by the NCAPH2 gene. CAP-H2 is a subunit of condensin II, a large protein complex involved in chromosome condensation.

A complete AB5 toxin complex contains six protein units. Five units are similar or identical in structure and they comprise the B subunit. The last protein unit is unique and is known as the A subunit. General diagram of the A subunit of the AB5 toxin with the disulfide linkage.

The IL6 receptor is a protein complex consisting of an IL-6 receptor subunit (IL6R) and interleukin 6 signal transducer Glycoprotein 130. IL6R also denotes the human gene encoding this subunit. Alternatively spliced transcript variants encoding distinct isoforms have been reported. IL6R subunit is also shared by many other cytokines.

Subunit beta of interleukin 12 (also known as IL-12B, natural killer cell stimulatory factor 2, cytotoxic lymphocyte maturation factor p40, or interleukin-12 subunit p40) is a protein that in humans is encoded by the IL12B gene. IL-12B is a common subunit of interleukin 12 and Interleukin 23.

This gene is one of two genes that encode the V1 domain C subunit proteins and is found ubiquitously. This C subunit is analogous but not homologous to gamma subunit of F-ATPases. Previously, this gene was designated ATP6D. In melanocytic cells ATP6V1C1 gene expression may be regulated by MITF.

Interleukin 10 receptor, alpha subunit is a subunit for the interleukin-10 receptor. IL10RA, is its human gene. IL10RA has also recently been designated CDW210A (cluster of differentiation W210A).

Two further studies then confirmed this interaction using radiolabeling and protein crystallization. It was further found, however, that amino acid changes within subunit a could also lower V-ATPase-Bafilomycin interaction, indicating a minor role of subunit a in bafilomycin binding in addition to subunit c. Overall, bafilomycin binds with nanomolar efficiency to the Vo c subunit of the V-ATPase complex. Specifically, bafilomycin interacts with the proteolipid ring of Vo, inhibiting proton translocation.

Retinal rod rhodopsin-sensitive cGMP 3',5'-cyclic phosphodiesterase subunit delta is an enzyme that in humans is encoded by the PDE6D gene. PDE6D was originally identified as a fourth subunit of rod cell-specific cGMP phosphodiesterase (PDE) (). The precise function of PDE delta subunit in the rod specific GMP-PDE complex is unclear. In addition, PDE delta subunit is not confined to photoreceptor cells but is widely distributed in different tissues.

Cholera toxin B pentamer, Vibrio cholerae. The cholera toxin is an oligomeric complex made up of six protein subunits: a single copy of the A subunit (part A, enzymatic, ), and five copies of the B subunit (part B, receptor binding, ), denoted as AB5. Subunit B binds while subunit A activates the G protein which activates adenylate cyclase. The three-dimensional structure of the toxin was determined using X-ray crystallography by Zhang et al.

This gene PSMB10 encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit. Proteolytic processing is required to generate a mature subunit. Expression of this gene is induced by gamma interferon, and this gene product replaces catalytic subunit beta2 (proteasome subunit beta type-7) in the immunoproteasome. The human PSMB10 gene has 8 exons and locates at chromosome band 16q22.1.

This gene encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit. This gene is located in the class II region of the MHC (major histocompatibility complex). Expression of this gene is induced by gamma interferon and this gene product replaces catalytic subunit 3 (proteasome beta 5 subunit) in the immunoproteasome. Proteolytic processing is required to generate a mature subunit.

The gene PSMB9 encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit. This gene is located in the class II region of the MHC (major histocompatibility complex). Expression of this gene is induced by gamma interferon and this gene product replaces catalytic subunit 1 (proteasome beta 6 subunit) in the immunoproteasome. Proteolytic processing is required to generate a mature subunit.

Glutamate-cysteine ligase, also known as gamma-glutamylcysteine synthetase is the first rate limiting enzyme of glutathione synthesis. The enzyme consists of two subunits, a heavy catalytic subunit and a light regulatory subunit. The gene encoding the catalytic subunit encodes a protein of 367 amino acids with a calculated molecular weight of 72.773 kDa and maps to chromosome 6. The regulatory subunit is derived from a different gene located on chromosome 1p22-p21.

This gene encodes a subunit of the N-methyl-D- aspartate (NMDAR) receptors, which belong to the superfamily of glutamate- regulated ion channels, and function in physiological and pathological processes in the central nervous system. This subunit shows greater than 90% identity to the corresponding subunit in rat. Studies in the knockout mouse deficient in this subunit suggest that this gene may be involved in the development of synaptic elements by modulating NMDA receptor activity.

Subunit 1 has tandemly repeated SURP motifs in its amino-terminal half while its carboxy- terminal half contains a proline-rich region and a ubiquitin-like domain. Binding studies with truncated subunit 1 derivatives demonstrated that the two SURP motifs are necessary for binding to subunit 3 while contacts with subunit 2 may occur through sequences carboxy-terminal to the SURP motifs. Alternative splicing results in multiple transcript variants encoding different isoforms.

Location of the MT-CO2 gene in the human mitochondrial genome. MT-CO2 is one of the three cytochrome c oxidase subunit mitochondrial genes (orange boxes). Cytochrome c oxidase subunit 2, also known as cytochrome c oxidase polypeptide II, is a protein that in humans is encoded by the MT-CO2 gene. Cytochrome c oxidase subunit II, abbreviated COXII, COX2, COII, or MT-CO2, is the second subunit of cytochrome c oxidase.

As shown, different ligands bind either the allosteric or the catalytic subunit. Allosteric subunit binds a non-substrate, activating FA (e.g., palmitic acid). The allosteric subunit with bound fatty acid activates the catalytic subunit by decreasing the Km for AA. PTGS2 (COX-2) exists as a homodimer, each monomer with a molecular mass of about 70 kDa. The tertiary and quaternary structures of PTGS1 (COX-1) and PTGS2 (COX-2) enzymes are almost identical.

General transcription factor IIE subunit 2 (GTF2E2), also known as transcription initiation factor IIE subunit beta (TFIIE-beta), is a protein that in humans is encoded by the GTF2E2 gene.

General transcription factor IIE subunit 1 (GTF2E1), also known as transcription initiation factor IIE subunit alpha (TFIIE-alpha), is a protein that in humans is encoded by the GTF2E1 gene.

Furthermore, the beta B subunit forms a homodimer, activin B, and also joins with the beta A subunit to form a heterodimer, activin AB, both of which stimulate FSH secretion.

In muscle, capping protein α1 subunit and β1 subunit are localized at the Z-disc, and form CapZ. CapZ interacts with α-actinin, nebulette, nebulin, HSC70. at the Z-disc.

26S proteasome non-ATPase regulatory subunit 2, also as known as 26S Proteasome Regulatory Subunit Rpn1 (systematic nomenclature), is an enzyme that in humans is encoded by the PSMD2 gene.

The beta subunit of CG is encoded by 6 genes which are arranged in tandem and inverted pairs on chromosome 19q13.3 and contiguous with the luteinizing hormone beta subunit gene.

Navα1.2, also known as the sodium channel, voltage-gated, type II, alpha subunit is a protein that in humans is encoded by the SCN2A gene. Functional sodium channels contain an ion conductive alpha subunit and one or more regulatory beta subunits. Sodium channels which contain the Navα1.2 subunit are called Nav1.2 channels.

The first proposes that the GTP-bound-Tα releases the PDE γ subunit from the catalytic subunits in order to activate hydrolysis. The second more likely mechanism proposes that binding causes a positional shift of the γ subunit, allowing better accessibility of the catalytic subunit for cGMP hydrolysis. The GTPase activity of Tα hydrolyzes GTP to GDP and changes the conformation of the Tα subunit, increasing its affinity to bind to the α and β subunits on the PDE. The binding of Tα to these larger subunits results in another conformational change in PDE and inhibits the hydrolysis ability of the catalytic subunit.

Even though the alpha and beta subunits of hexosaminidase A can both cleave GalNAc residues, only the alpha subunit is able to hydrolyze GM2 gangliosides. The alpha subunit contains a key residue, Arg-424, which is essential for binding the N-acetyl-neuramanic residue of GM2 gangliosides. The alpha subunit can hydrolyze GM2 gangliosides because it contains a loop structure consisting of the amino acids: Gly-280, Ser-281, Glu-282, and Pro-283. The loop is absent in the beta subunit, but it serves as an ideal structure for the binding of the GM2 activator protein (GM2AP) in the alpha subunit.

Succinyl-CoA ligase [ADP-forming] subunit beta, mitochondrial (SUCLA2), also known as ADP-forming succinyl-CoA synthetase (SCS-A), is an enzyme that in humans is encoded by the SUCLA2 gene on chromosome 13. Succinyl-CoA synthetase (SCS) is a mitochondrial matrix enzyme that acts as a heterodimer, being composed of an invariant alpha subunit and a substrate-specific beta subunit. The protein encoded by this gene is an ATP-specific SCS beta subunit that dimerizes with the SCS alpha subunit to form SCS-A, an essential component of the tricarboxylic acid cycle. SCS-A hydrolyzes ATP to convert succinyl-CoA to succinate.

Calcium-activated potassium channel subunit beta-4 is a protein that in humans is encoded by the KCNMB4 gene. MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which slows activation kinetics, leads to steeper calcium sensitivity, and shifts the voltage range of current activation to more negative potentials than does the beta 1 subunit.

The CB subunit is a phospholipase A2 protein. The C-terminal (C-terminus) of the CB subunit is important for the interaction between both subunits as it interacts with an alpha helix of CA. The CA subunit thereby blocks a part of the enzyme surface of phospholipase A2, resulting in an impossibility to be activated. This means the phospholipase A2 cannot adsorb onto a lipid/water interface from the cell membrane. Residues on the CB subunit which are involved in the enzyme surface and blocked by the CA subunit are F24 and F119, which are phenylalanine amino acids.

This gene is a member of the glycoprotein hormone beta chain family and encodes the beta 5 subunit of chorionic gonadotropin (CG). Glycoprotein hormones are heterodimers consisting of a common alpha subunit and a unique beta subunit which confers biological specificity. CG is produced by the trophoblastic cells of the placenta and stimulates the ovaries to synthesize the steroids that are essential for the maintenance of pregnancy. The beta subunit of CG is encoded by 6 genes which are arranged in tandem and inverted pairs on chromosome 19q13.3 and contiguous with the luteinizing hormone beta subunit gene.

In E. coli CPSI is a heterodimer with a small subunit and a larger subunit with about 382 and 1073 amino acid residues in size, although in mammals (and other vertebrates) the CPSI protein is encoded by a single gene. The small subunit contains one active site for the binding and deamination of glutamine to make ammonia and glutamate. The large subunit contains two active sites, one for the production of carboxyphosphate, and the other for the production of carbamoyl phosphate. Within the large subunit there are two domains (B and C) each with an active site of the ATP-grasp family.

The large subunit of TFIIF (RAP74) stimulates the CTD phosphatase activity, whereas TFIIB inhibits TFIIF-mediated stimulation. Dephosphorylation of the CTD alters the migration of the largest subunit of RNAPII (RPB1).

The interleukin 11 receptor is a type I cytokine receptor, binding interleukin 11. It is a heterodimer composed of an interleukin 11 receptor alpha subunit and an incompletely characterized beta subunit.

The Glycine receptor subunit alpha-3 is a protein that in humans is encoded by the GLRA3 gene. The protein encoded by this gene is a subunit of the glycine receptor.

The ~45kDa beta subunit has nine transmembrane segments which serve to couple the decarboxylation of the carboxybiotin to the translocation of Na+ from the cytoplasm to the periplasm. The small ~9kDa gamma subunit is an integral membrane protein with a single helix at the N-terminus, followed by a hydrophilic C-terminal domain which interacts with the alpha subunit. The gamma subunit is essential for the overall stability of the complex, and likely serves as an anchor to hold the alpha and beta subunits in place. Furthermore, the gamma subunit significantly accelerates the rate of oxaloacetate decarboxylation in the alpha subunit, and this correlates with the coordination of a Zn2+ metal ion by several residues at the hydrophilic C-terminus.

The maturation of the pre-60S subunit into a mature 60S subunit requires many biogenesis factors that associate and disassociate. In addition, some assembly factors associate with the 60S subunit while others only interact with it transiently. As an overall trend, the maturation of the pre-60S subunit is marked a gradual decrease in complexity. The subunit matures as it moves from the nucleolus to the cytoplasm and gradually the number of trans-acting factors are reduced. The maturation of the 60S subunit requires the help of about 80 factors. Eight of these factors are directly involved with the processing of the 27S A3 pre- rRNA, which actually completes the formation of the mature 5’end of the 5.8S rRNA.

When another subunit binds the hydrophobic cleft it binds in a P5-P2 anti-parallel fashion creating the most energetically favourable conformation of a true Ig-fold. When a chaperone/subunit complex is brought to the growing usher/pilus complex (note that a chaperone/subunit complex forms the base of this) the NTD and CTDs of the usher dimer bring and hold the chaperone/subunit complex to the pilus base. Here the N-terminal extension of the subunit interacts with the free P5 pocket of the pilus. This binding causes a residue by residue 'unzipping' of the chaperone's G1 strand with concurrent 'zipping' of the N-terminal extension of the chaperone/subunit complex, unknown as the zip in-zip out mechanism.

The product of this gene belongs to the Protein phosphatase 2A regulatory subunit B family. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

HLA-DP is an αβ-heterodimer cell-surface receptor. Each DP subunit (α-subunit, β-subunit) is composed of a α-helical N-terminal domain, an IgG-like β-sheet, a membrane spanning domain, and a cytoplasmic domain. The α-helical domain forms the sides of the peptide binding groove. The β-sheet regions form the base of the binding groove and the bulk of the molecule as well as the inter-subunit (non-covalent) binding region.

However, when it bonds to the second subunit of myosin phosphatase, MYPT1 (MW ~130 kDa), this catalytic cleft changes configuration. This results in a dramatic increase in myosin specificity. Thus, it is clear that MYPT1 has great regulatory power over PP1 and myosin phosphatase, even without the presence of other activators or inhibitors. The third subunit, M20 (not to be confused with MLC20, the critical regulatory subunit of myosin), is the smallest and most mysterious subunit.

These gradients are essential for osmoregulation, for sodium-coupled transport of a variety of organic and inorganic molecules, and for electrical excitability of nerve and muscle. This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The beta subunit regulates, through assembly of alpha/beta heterodimers, the number of sodium pumps transported to the plasma membrane. The glycoprotein subunit of Na+/K+ -ATPase is encoded by multiple genes.

The B subunit has little interaction with the catalytic subunit but also contains an acidic substrate binding site positioned near the active site of the catalytic subunit (Janssens & Goris, 2001). The B subunits share no sequence identity with B' subunits (Janssens & Goris, 2001). CAPPs can be present as the core dimeric enzyme of AC or a trimeric holoenzyme of ABC or AB’C (Janssens & Goris, 2001). Ceramide has also been shown to activate the C subunit alone (Janssens & Goris, 2001).

LQT5 is caused by variants in the KCNE1 gene responsible for the potassium channel beta subunit MinK. This subunit, in conjunction with the alpha subunit encoded by KCNQ1, is responsible for the potassium current IKs which is decreased in LQTS. LQT6 is caused by variants in the KCNE2 gene responsible for the potassium channel beta subunit MiRP1 which generates the potassium current IKr. Variants that decrease this current have been associated with prolongation of the QT interval.

The protein encoded by this gene is one subunit of a trimeric complex, forming a highly conserved transcription factor that binds with high specificity to CCAAT motifs in the promoter regions in a variety of genes. This gene product, subunit B, forms a tight dimer with the C subunit, a prerequisite for subunit A association. The resulting trimer binds to DNA with high specificity and affinity. Subunits B and C each contain a histone-like motif.

The product of this gene belongs to the phosphatase 2A regulatory subunit B family. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

The product of this gene belongs to the phosphatase 2 regulatory subunit B family. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

The product of this gene belongs to the phosphatase 2A regulatory subunit B family. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

The protein encoded by this gene is one subunit of a trimeric complex, forming a highly conserved transcription factor that binds with high specificity to CCAAT motifs in the promoter regions in a variety of genes. This gene product, subunit C, forms a tight dimer with the B subunit (NFYB), a prerequisite for subunit A (NFYA) association. The resulting trimer binds to DNA with high specificity and affinity. Subunits B and C each contain a histone-like motif.

The product of this gene belongs to the phosphatase 2 regulatory subunit B family. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

The product of this gene belongs to the phosphatase 2A regulatory subunit B family. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity.

The H+/K+ ATPase is a heterodimeric protein, the product of 2 genes. The gene ATP4AATP4A ATPase H+/K+ transporting alpha subunit encodes the H+/K+ ATPase α subunit, and is an ~1000-amino acid protein that contains the catalytic sites of the enzyme and forms the pore through the cell membrane that allows the transport of ions. Hydronium ions bind to two active sites present in the α subunit. The α subunit also has a phosphorylation site (Asp385).

Condensin complex subunit 1 also known as chromosome-associated protein D2 (CAP-D2) or non-SMC condensin I complex subunit D2 (NCAPD2) or XCAP-D2 homolog is a protein that in humans is encoded by the NCAPD2 gene. CAP-D2 is a subunit of condensin I, a large protein complex involved in chromosome condensation.

Enolase is a member of the large enolase superfamily. It has a molecular weight of 82,000-100,000 Daltons depending on the isoform. In human alpha enolase, the two subunits are antiparallel in orientation so that Glu20 of one subunit forms an ionic bond with Arg414 of the other subunit. Each subunit has two distinct domains.

Bacterial initiation factor 1 is a bacterial initiation factor. IF1 associates with the 30S ribosomal subunit in the A site and prevents an aminoacyl-tRNA from entering. It modulates IF2 binding to the ribosome by increasing its affinity. It may also prevent the 50S subunit from binding, stopping the formation of the 70S subunit.

COXI, COXII, and COXIII (orange boxes). Cytochrome c oxidase has 3 subunits which are encoded by mitochondrial DNA (cytochrome c oxidase subunit I, subunit II, and subunit III). Of these 3 subunits encoded by mitochondrial DNA, two have been identified in extramitochondrial locations. In pancreatic acinar tissue, these subunits were found in zymogen granules.

EIF6 helps to protect mature 60s subunit and then EIF6 should disassociate with 60s subunit so that it can binds to 40s subunit to form ribosome. Keeping in balance of EIF6 is essential for the body: few EIF6 helps synthesis of normal ribosome, while large amount of EIF6 inhibited 60s subunits bind to 40s subunits.

RPA is a heterotrimer, composed of the subunits RPA1 (70kDa subunit), RPA2 (32kDa subunit) and RPA3 (14kDa subunit). The three RPA subunits contain four OB- folds (oligonucleotide/oligosaccharide binding) that bind RPA to single- stranded DNA. RPA shares many features with the CST complex heterotrimer, although RPA has a more uniform 1:1:1 stoichiometry.

The SCO2 gene encodes for a protein essential for the assembly and function of Mammalian cytochrome c oxidase (COX)(Complex IV) of the mitochondrial respiratory chain. SCO2 acts as a metallochaperone involved in the biogenesis of cytochrome c oxidase subunit II, an essential subunit of Complex IV which transfers the electrons from cytochrome c to the bimetallic center of the catalytic subunit 1 via its binuclear copper A center. The biogenesis involves the transport of copper to the Cu(A) site on the cytochrome c oxidase subunit II leading to the proper synthesis and maturation of the subunit. In addition, SCO2 acts as a thiol-disulfide oxidoreductase to regulate the redox state of the cysteines in SCO1 during maturation of the cytochrome c oxidase subunit II. The maturation and synthesis of cytochrome c oxidase subunit II is required for the function of Mammalian cytochrome c oxidase (COX)(Complex IV).

This subunit is only involved in activity and not in assembly. This subunit also acts as an inhibitor of free V1 subunits; it stops ATP hydrolysis when V1 and Vo are dissociated.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L24P family of ribosomal proteins.

Neuronal acetylcholine receptor subunit alpha-9, also known as nAChRα9, is a protein that in humans is encoded by the CHRNA9 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR). α9 subunit-containing receptors are notably blocked by nicotine. The role of this antagonism in the effects of tobacco are unknown.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L34E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L13E family of ribosomal proteins.

The receptor for interleukin-4 is known as the IL-4Rα. This receptor exists in 3 different complexes throughout the body. Type 1 receptors are composed of the IL-4Rα subunit with a common γ chain and specifically bind IL-4. Type 2 receptors consist of an IL-4Rα subunit bound to a different subunit known as IL-13Rα1.

The IL-5 receptor is composed of an α and a βc chain. The α subunit is specific for the IL-5 molecule, whereas the βc subunit also recognised by interleukin 3 (IL3) and granulocyte-macrophage colony-stimulating factor (GM- CSF). Glycosylation of the Asn196 residue of the Rα subunit appears to be essential for binding of IL-5.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S10E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S21E family of ribosomal proteins.

The peripheral stalk differs in subunit composition between mitochondrial, chloroplast and bacterial F-ATPases. In bacterial and chloroplast F-ATPases, the peripheral stalk is composed of one copy of the delta subunit (homologous to OSCP in mitochondria), and two copies of subunit b in bacteria, or one copy each of subunits b and b' in chloroplasts and photosynthetic bacteria.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L29P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L23P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L38E family of ribosomal proteins.

Voltage-gated calcium channels are made up of several subunits. The α1 subunit is the primary subunit that forms the transmembrane pore of the channel. The α1 subunit also determines the type of calcium channel. The β, α2δ, and γ subunits, present in only some types of calcium channels, are auxiliary subunits that play secondary roles in the channel.

The 30S subunit is the target of antibiotics such as tetracycline and gentamicin. These antibiotics specifically target the prokaryotic ribosomes, hence their usefulness in treating bacterial infections in eukaryotes. Tetracycline interacts with H27 in the small subunit as well as binding to the A-site in the large subunit. Puromycin is an inhibitor of ribosomal translation.

Rpo3 is notable in that it's an iron–sulfur protein. RNAP I/III subunit AC40 found in some eukaryotes share similar sequences, but does not bind iron. This domain, in either case, serves a structural function. Archaeal RNAP subunit previously used an "RpoX" nomenclature where each subunit is assigned a letter in a way unrelated to any other systems.

The heterodimer interface is predominantly found between domain IV and the small subunit, which is also a calmodulin-like calcium-binding domain. This gene encodes a large subunit. It is an atypical calpain in that it lacks the calmodulin-like calcium-binding domain and instead has a divergent C-terminal domain. It therefore cannot heterodimerize with the small subunit.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L18P family of ribosomal proteins.

The gene PMSA6 encodes a member of the peptidase T1A family, that is a 20S core alpha subunit. A pseudogene has been identified on the Y chromosome. The gene has 8 exons and locates at chromosome band 14q13. The human protein proteasome subunit alpha type-6 is also known as 20S proteasome subunit alpha-1 (based on systematic nomenclature).

The subunit Rpn12 incorporated into 19S regulatory particle when 19S lid and base bind together. Recent evidence of crystal structures of proteasomes isolated from Saccharomyces cerevisiae suggests that the catalytically active subunit Rpn8 and subunit Rpn11 form heterodimer. The data also reveals the details of the Rpn11 active site and the mode of interaction with other subunits.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S19E family of ribosomal proteins.

The pituitary glycoprotein hormone family includes follicle-stimulating hormone, luteinizing hormone, chorionic gonadotropin, and thyroid-stimulating hormone. All of these glycoproteins consist of an identical alpha subunit and a hormone-specific beta subunit. This gene encodes the beta subunit of follicle-stimulating hormone. In conjunction with luteinizing hormone, follicle-stimulating hormone induces egg and sperm production.

Interleukin 12 receptor, beta 2 subunit is a subunit of the interleukin 12 receptor. IL12RB2 is its human gene. IL12RB2 orthologs have been identified in all mammals for which complete genome data are available. The protein encoded by this gene is a type I transmembrane protein identified as a subunit of the interleukin 12 receptor complex.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L11P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a cytoplasmic ribosomal protein that is a component of the 60S subunit. The protein belongs to the L22E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L28E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L10E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a cytoplasmic ribosomal protein that is a component of the 60S subunit. The protein belongs to the L29E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S15P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S27E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L30P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L5P family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L14E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L31E family of ribosomal proteins.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit. The protein belongs to the S26E family of ribosomal proteins.

The gene for the alpha subunit is located on chromosome 6q12.21. The luteinizing hormone beta subunit gene is localized in the LHB/CGB gene cluster on chromosome 19q13.32. In contrast to the alpha gene activity, beta LH subunit gene activity is restricted to the pituitary gonadotropic cells. It is regulated by the gonadotropin-releasing hormone from the hypothalamus.

Such "multi-subunit" assemblies usually involve a circular arrangement of identical or homologous proteins closely packed around a water-filled pore through the plane of the membrane or lipid bilayer. For most voltage-gated ion channels, the pore-forming subunit(s) are called the α subunit, while the auxiliary subunits are denoted β, γ, and so on.

N-terminal glycosylation of receptor subunits is critical for subunit assembly and plasma membrane trafficking. Figure 2. The subunits are assembled as a pentamer (right) and each subunit has four transmembrane domains (left).

Voltage-gated potassium channel subunit beta-3 is a protein that in humans is encoded by the KCNAB3 gene. The protein encoded by this gene is a voltage- gated potassium channel beta subunit.

Gamma-aminobutyric acid receptor subunit rho-3 is a protein that in humans is encoded by the GABRR3 gene. The protein encoded by this gene is a subunit of the GABAA-ρ receptor.

It is also known as minK (minimal potassium channel subunit).

Cytolethal distending toxins are classified as AB toxins, with an active ("A") subunit that directly damages DNA and a binding ("B") subunit that helps the toxin attach to the target cells. CdtB is the active subunit and a homolog to mammalian DNase I, whereas CdtA and CdtC make up the binding subunit. Cytolethal distending toxins are produced by gram-negative pathogenic bacteria from the phylum Proteobacteria. Many of these bacteria, including Shigella dysenteriae, Haemophilus ducreyi, and Escherichia coli, infect humans.

In molecular biology, the cyclin-dependent kinase regulatory subunit family is a family of proteins consisting of the regulatory subunits of cyclin-dependent protein kinases. In eukaryotes, cyclin-dependent protein kinases interact with cyclins to regulate cell cycle progression, and are required for the G1 and G2 stages of cell division. The proteins bind to a regulatory subunit, cyclin- dependent kinase regulatory subunit (CKS), which is essential for their function. This regulatory subunit is a small protein of 79 to 150 residues.

Streptomycin is a protein synthesis inhibitor. It binds to the small 16S rRNA of the 30S subunit of the bacterial ribosome, interfering with the binding of formyl-methionyl-tRNA to the 30S subunit. This leads to codon misreading, eventual inhibition of protein synthesis and ultimately death of microbial cells through mechanisms that are still not understood. Speculation on this mechanism indicates that the binding of the molecule to the 30S subunit interferes with 50S subunit association with the mRNA strand.

DNA primase large subunit is an enzyme that in humans is encoded by the PRIM2 gene. The replication of DNA in eukaryotic cells is carried out by a complex chromosomal replication apparatus, in which DNA polymerase alpha and primase are two key enzymatic components. Primase, which is a heterodimer of a small subunit and a large subunit, synthesizes small RNA primers for the Okazaki fragments made during discontinuous DNA replication. The protein encoded by this gene is the large, 58 kDa primase subunit.

Calcium-activated potassium channel subunit beta-2 is a protein that in humans is encoded by the KCNMB2 gene. Big Potassium (BK) channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. BK channels can contain two distinct subunits: a pore-forming alpha subunit and a modulatory beta subunit. Each complete BK channel contains four copies of the pore-forming alpha subunit and up to four beta subunits.

Troponin C, skeletal muscle is a protein that in humans is encoded by the TNNC2 gene. Troponin (Tn), a key protein complex in the regulation of striated muscle contraction, is composed of 3 subunits. The Tn-I subunit inhibits actomyosin ATPase, the Tn-T subunit binds tropomyosin and Tn-C, while the Tn-C subunit binds calcium and overcomes the inhibitory action of the troponin complex on actin filaments. The protein encoded by this gene is the Tn-C subunit.

Like the other class IA PI3Ks, p110δ is a catalytic subunit, whose activity and subcellular localisation are controlled by an associated p85α, p55α, p50α or p85β regulatory subunit. The p55γ regulatory subunit is not thought to be expressed at significant levels in immune cells. There is no evidence for selective association between p110α, p110β or p110δ for any particular regulatory subunit. The class IA regulatory subunits (collectively referred to here as p85) bind to proteins that have been phosphorylated on tyrosines.

All ribosomal proteins have been isolated and many specific antibodies have been produced. These, together with electronic microscopy and the use of certain reactives, have allowed for the determination of the topography of the proteins in the ribosome. E. coli, other bacteria and Archaea have a 30S small subunit and a 50S large subunit, whereas humans and yeasts have a 40S small subunit and a 60S large subunit. Equivalent subunits are frequently numbered differently between bacteria, Archaea, yeasts and humans.

Choriogonadotropin subunit beta is a protein that in humans is encoded by the CGB7 gene. This gene is a member of the glycoprotein hormone beta chain family and encodes the beta 7 subunit of chorionic gonadotropin (CG). Glycoprotein hormones are heterodimers consisting of a common alpha subunit and a unique beta subunit which confers biological specificity. CG is produced by the trophoblastic cells of the placenta and stimulates the ovaries to synthesize the steroids that are essential for the maintenance of pregnancy.

Cytochrome c1, heme protein, mitochondrial (CYC1), also known as UQCR4, MC3DN6, Complex III subunit 4, Cytochrome b-c1 complex subunit 4, or Ubiquinol-cytochrome-c reductase complex cytochrome c1 subunit is a protein that in humans is encoded by the CYC1 gene. CYC1 is a respiratory subunit of Ubiquinol Cytochrome c Reductase (complex III), which is located in the inner mitochondrial membrane and is part of the electron transport chain. Mutations in this gene may cause mitochondrial complex III deficiency, nuclear, type 6.

Sodium channel subunit beta-1 is a protein that in humans is encoded by the SCN1B gene. Voltage-gated sodium channels are essential for the generation and propagation of action potentials in striated muscle and neuronal tissues. Biochemically, they consist of a large alpha subunit and 1 or 2 smaller beta subunits, such as SCN1B. The alpha subunit alone can exhibit all the functional attributes of a voltage-gated Na+ channel, but requires a beta-1 subunit for normal inactivation kinetics.

The BCKDHA gene encodes the alpha subunit of E1, and the BCKDHB gene (MIM 248611) encodes the beta subunit of E1.[supplied by OMIM] The normal function of the BCKDHA gene is to provide instructions for making the alpha subunit of the branched-chain alpha-keto dehydrogenase (BCKD) enzyme complex. The alpha subunit is one part of the BCKD enzyme complex. Two beta subunits are produced from the BCKDHB gene and connect to two alpha subunits to form the E1 (decarboxylase) component.

The structure of the 40S subunit revealed that the eukaryote-specific proteins (rpS7, rpS10, rpS12 and RACK1), as well as numerous eukaryote-specific extensions of proteins, are located on the solvent-exposed side of the small subunit. Here, they participate in the stabilization of rRNA expansion segments. Moreover, the beak of the 40S subunit is remodeled, as rRNA has been replaced by proteins rpS10 and rpS12. As observed for the 40S subunit, all eukaryote-specific proteins of the 60S subunit (RPL6, RPL22, RPL27, RPL28, RPL29 and RPL36) and many extensions are located at the solvent-exposed side, forming an intricate network of interactions with eukaryotic-specific RNA expansion segments.

Chemokines also stimulate an I-like domain on the beta subunit, which causes the MIDAS site on the beta subunit to bind to glutamate on the I domain of the alpha subunit. This binding process causes the beta subunit to pull down the alpha 7 helix of the I domain, exposing and opening up the MIDAS site on the alpha subunit for binding. This causes LFA-1 to undergo a conformational change to the fully extended conformation. The process of activating LFA-1 is known as inside out signaling, which causes LFA-1 to shift from low affinity to high affinity by opening the ligand-binding site.

The Shine-Delgarno sequence binds to a complementary pyrimidine-rich sequence on the 3' end of the 16S rRNA part of the 30S ribosomal subunit. The binding of these complementary sequences ensures that the 30S ribosomal subunit is bound to the mRNA and is aligned such that the initiation codon is placed in the 30S portion of the P-site. Once the mRNA and 30S subunit are properly bound, an initiation factor brings the initiator tRNA-amino acid complex, f-Met-tRNA, to the 30S P site. The initiation phase is completed once a 50S subunit joins the 30 subunit, forming an active 70S ribosome.

In eukaryotes and archaea, the amino acid encoded by the start codon is methionine. The Met-charged initiator tRNA (Met-tRNAiMet) is brought to the P-site of the small ribosomal subunit by eukaryotic initiation factor 2 (eIF2). It hydrolyzes GTP, and signals for the dissociation of several factors from the small ribosomal subunit, eventually leading to the association of the large subunit (or the 60S subunit). The complete ribosome (80S) then commences translation elongation. Regulation of protein synthesis is partly influenced by phosphorylation of eIF2 (via the α subunit), which is a part of the eIF2-GTP-Met-tRNAiMet ternary complex (eIF2-TC).

Serine/threonine-protein phosphatase 2A regulatory subunit B' is an enzyme that in humans is encoded by the PPP2R4 gene. Protein phosphatase 2A is one of the four major Ser/Thr phosphatases and is implicated in the negative control of cell growth and division. Protein phosphatase 2A holoenzymes are heterotrimeric proteins composed of a structural subunit A, a catalytic subunit C, and a regulatory subunit B. The regulatory subunit is encoded by a diverse set of genes that have been grouped into the B/PR55, B'/PR61, and B/PR72 families. These different regulatory subunits confer distinct enzymatic specificities and intracellular localizations to the holozenzyme.

The alpha-subunit is the catalytic unit and contains regions characteristic of serine/threonine protein kinases. The beta-subunit is believed to be regulatory, possessing an N-terminal auto- phosphorylation site, an internal acidic domain, and a potential metal-binding motif. The beta subunit is a highly conserved protein of about 25kDa that contains, in its central section, a cysteine-rich motif, CX(n)C, that could be involved in binding a metal such as zinc. The mammalian beta-subunit gene promoter shares common features with those of other mammalian protein kinases and is closely related to the promoter of the regulatory subunit of cAMP- dependent protein kinase.

POLG is a gene that codes for the catalytic subunit of the mitochondrial DNA polymerase, called DNA polymerase gamma.Entrez Gene: POLG polymerase (DNA directed), gamma, catalytic subunit The human POLG cDNA and gene were cloned and mapped to chromosome band 15q25. In eukaryotic cells, the mitochondrial DNA is replicated by DNA polymerase gamma, a trimeric protein complex composed of a catalytic subunit, POLG, and a dimeric accessory subunit of 55 kDa encoded by the POLG2 gene. The catalytic subunit contains three enzymatic activities, a DNA polymerase activity, a 3’-5’ exonuclease activity that proofreads misincorporated nucleotides, and a 5’-dRP lyase activity required for base excision repair.

The Gβγ subunit plays a variety of roles in cell signalling processes and as such researchers are now examining its potential as a therapeutic drug target for the treatment of many medical conditions. However, it is recognized that there are a number of considerations to keep in mind when designing a drug which targets the Gβγ subunit: # The Gβγ subunit is essential for the formation of heterotrimeric G protein through its association with the Gα subunit allowing the G proteins coupling to the GPCR. Therefore, any agent inhibiting the Gβγ subunits signalling effects must not interfere with the heterotrimeric G protein formation or Gα subunit signalling. # Gβγ expression is universal throughout almost all the cells of the body so any agent acting to inhibit this subunit could elicit numerous side effects.

This gene is a member of the neuronal calcium channel gamma subunit gene subfamily of the PMP-22/EMP/MP20 family and is located in a cluster with two similar gamma subunit-encoding genes.

Resistance to this class of antibiotics usually results from genetic mutation in the gyrB subunit. Other mechanisms include de novo synthesis of a coumarin-resistant gyrase B subunit by the novobiocin producer S. sphaeroides .

Both subunits contain dozens of ribosomal proteins arranged on a scaffold composed of ribosomal RNA (rRNA). The small subunit monitors the complementarity between tRNA anticodon and mRNA, while the large subunit catalyzes peptide bond formation.

DNA polymerase delta subunit 4, also known as DNA polymerase delta subunit p12, is a protein that in humans is encoded by the POLD4 gene. It is a component of the DNA polymerase delta complex.

Calcium/calmodulin-dependent protein kinase type II subunit alpha (CAMKIIα), protein kinase , is one subunit of CamKII, a protein kinase (i.e., an enzyme which phosphorylates proteins) that in humans is encoded by the CAMK2A gene.

The DDB1 gene encodes the large subunit of DNA damage-binding protein, a heterodimer composed of a large and a small (DDB2) subunit. DDB1 contains 1140 amino acids, amounting to a mass of 127 kDa.

Thyrotropin-stimulating hormone (TSH) is a noncovalently linked glycoprotein heterodimer and is part of a family of pituitary hormones containing a common alpha subunit (TSHA) and a unique beta subunit (this protein) that confers specificity.

One of four equivalent subunit of the M12O40 cage in metatungstate.

Further narrowing bafilomycin's interaction site, they found that specific addition of just Vo subunit a could restore function. This suggested bafilomycin interacted specifically with subunit a of V-ATPase; however, another study contradicted this finding. A group found that by using a bafilomycin affinity chromatography column V-ATPase could be purified, and that addition of DCCD, an inhibitor of the Vo c subunit, drastically decreased bafilomycin's affinity for V-ATPase. This suggested that bafilomycin interacted more strongly with subunit c of the Vo domain.

Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial (SDHB) also known as iron-sulfur subunit of complex II (Ip) is a protein that in humans is encoded by the SDHB gene. The succinate dehydrogenase (also called SDH or Complex II) protein complex catalyzes the oxidation of succinate (succinate + ubiquinone => fumarate + ubiquinol). SDHB is one of four protein subunits forming succinate dehydrogenase, the other three being SDHA, SDHC and SDHD. The SDHB subunit is connected to the SDHA subunit on the hydrophilic, catalytic end of the SDH complex.

The protein encoded by this gene is the alpha-3 subunit of one of several alpha/beta-subunit heterodimeric transcription factors that regulate many adaptive responses to low oxygen tension (hypoxia). The alpha-3 subunit lacks the transactivation domain found in factors containing either the alpha-1 or alpha-2 subunits. It is thought that factors containing the alpha-3 subunit are negative regulators of hypoxia-inducible gene expression. At least three transcript variants encoding three different isoforms have been found for this gene.

Missense mutations in the dnaQ gene lead to the induction of the SOS DNA repair mechanism. Mutating the essential amino acid in the catalytic center of the ε subunit leads to complete loss of function. Overexpression of the ε subunit decreases the incidence of mutations with exposure to UV, proving that the epsilon subunit has an essential function in DNA editing and preventing the initiation of SOS DNA repair. The ε subunit has also been proven to have some impact on the growth rate of E. coli.

The structure of the trimeric human H2 complex, with the catalytic A subunit in blue, the structural B subunit in brown, and the structural C subunit in pink. Although the B and C subunits do not interact with the active site, they are required for activity. The catalytic residues in the active site are shown in magenta. Positions shown in yellow are those with known AGS mutations. The most common AGS mutation - alanine to threonine at position 177 of subunit B - is shown as a green sphere.

The binding of the large subunit causes a conformational change in the 70S, which opens another site for protein translation. In order to form the translation complex with the 50S subunit, the 30S subunit must bind IF-1, IF-2, IF-3, mRNA, and f-met- tRNA. Next, the 50S subunit binds and a guanosine triphosphate is cleaved to guanosine diphosphate and inorganic phosphate, thus dissociating the initiation factors and resulting in protein translation. This process is called "initiation" and is the slowest process of translation.

DNA-directed RNA polymerase II subunit RPB9 is an enzyme that in humans is encoded by the POLR2I gene. This gene encodes a subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. This subunit, in combination with two other polymerase subunits, forms the DNA binding domain of the polymerase, a groove in which the DNA template is transcribed into RNA. The product of this gene has two zinc finger motifs with conserved cysteines and the subunit does possess zinc binding activity.

Recombinant factor XIII (rFXIII) is the only drug alternative to receiving blood transfusions, the traditional treatment for factor XIII deficiency. Novo Nordisk’s rFXIII, catridecacog, was approved by the US Food and Drug Administration in 2014. Although it is a recombinant protein, rFXIII subunit A is identical in structure and function to the A subunit of factor XIII naturally produced in the body by healthy individuals. These patients need exogenous subunit A of factor XIII since they have a mutation which prevents production of the A subunit.

AMP-activated protein kinase (AMPK) is a heterotrimeric protein composed of a catalytic alpha subunit, a noncatalytic beta subunit, and a noncatalytic regulatory gamma subunit. Various forms of each of these subunits exist, encoded by different genes. AMPK is an important energy-sensing enzyme that monitors cellular energy status and functions by inactivating key enzymes involved in regulating de novo biosynthesis of fatty acid and cholesterol. This gene is a member of the AMPK gamma subunit family and encodes a protein with four CBS domains.

The gene PSMB6 encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit in the proteasome. This catalytic subunit is not present in the immunoproteasome and is replaced by catalytic inducible subunit beta1i (proteasome beta 9 subunit). The proteasomes are an pivotal component for the Ubiquitin-Proteasome System (UPS) and corresponding cellular Protein Quality Control (PQC). Compromised proteasome complex assembly leads to reduced proteolytic activities and accumulation of damaged or misfolded protein species.

60S ribosomal protein L37 is a protein that in humans is encoded by the RPL37 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L37a is a protein that in humans is encoded by the RPL37A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L27a is a protein that in humans is encoded by the RPL27A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L39 is a protein that in humans is encoded by the RPL39 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L15 is a protein that in humans is encoded by the RPL15 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L27 is a protein that in humans is encoded by the RPL27 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L41 is a protein that in humans is encoded by the RPL41 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S12 is a protein that in humans is encoded by the RPS12 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S15 is a protein that in humans is encoded by the RPS15 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S8 is a protein that in humans is encoded by the RPS8 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S11 is a protein that in humans is encoded by the RPS11 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S23 is a protein that in humans is encoded by the RPS23 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S28 is a protein that in humans is encoded by the RPS28 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

The α/β-barrel structure is capped on one side by the N-terminal helix. The other side, the carboxylic side, contains the active site. Each subunit contains a phosphate-ion bound in position of the aldolase biding site. It has been found that there are four cysteinyl groups present in each subunit, with two readily accessible and two buried in the subunit.

NAD(+)-dependent isocitrate dehydrogenases catalyze the allosterically regulated rate-limiting step of the tricarboxylic acid cycle. Each isozyme is a heterotetramer that is composed of two alpha subunits, one beta subunit, and one gamma subunit. The protein encoded by this gene is the gamma subunit of one isozyme of NAD(+)-dependent isocitrate dehydrogenase. This gene is a candidate gene for periventricular heterotopia.

60S ribosomal protein L10a is a protein that in humans is encoded by the RPL10A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L36 is a protein that in humans is encoded by the RPL36 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of four RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L21 is a protein that in humans is encoded by the RPL21 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L24 is a protein that in humans is encoded by the RPL24 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L36a is a protein that in humans is encoded by the RPL36A gene. Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S17 is a protein that in humans is encoded by the RPS17 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

60S ribosomal protein L13a is a protein that in humans is encoded by the RPL13A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S24 is a protein that in humans is encoded by the RPS24 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

This gene encodes the subunit of a collagen-like molecule associated with acetylcholinesterase in skeletal muscle. Each molecule is composed of three identical subunits. Each subunit contains a proline-rich attachment domain (PRAD) that binds an acetylcholinesterase tetramer to anchor the catalytic subunit of the enzyme to the basal lamina. Multiple transcript variants encoding different isoforms have been found for this gene.

60S ribosomal protein L23 is a protein that in humans is encoded by the RPL23 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L8 is a protein that in humans is encoded by the RPL8 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L19 is a protein that in humans is encoded by the RPL19 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L35a is a protein that in humans is encoded by the RPL35A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L18 is a protein that in humans is encoded by the RPL18 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S18 is a protein that in humans is encoded by the RPS18 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

Guanine nucleotide-binding protein subunit beta-4 is a protein that in humans is encoded by the GNB4 gene. Heterotrimeric guanine nucleotide-binding proteins (G proteins), which integrate signals between receptors and effector proteins, are composed of an alpha, a beta, and a gamma subunit. These subunits are encoded by families of related genes. This gene encodes a beta subunit.

40S ribosomal protein S20 is a protein that in humans is encoded by the RPS20 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

The enzyme weighs 14 kDa and is composed of 129 amino acids.] The protein is a subunit of Complex IV, which consists of 13 mitochondrial- and nuclear-encoded subunits. The sequence of subunit Vb is well conserved and includes three conserved cysteines that coordinate the zinc ion. Two of these cysteines are clustered in the C-terminal section of the subunit.

60S ribosomal protein L9 is a protein that in humans is encoded by the RPL9 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L17 is a protein that in humans is encoded by the RPL17 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L30 is a protein that in humans is encoded by the RPL30 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S15a is a protein that in humans is encoded by the RPS15A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

The active site is formed by the center of the β subunit flanked by part of the α subunit. Farnesyltransferase coordinates a zinc cation on its β subunit at the lip of the active site. Farnesyltransferase has a hydrophobic binding pocket for farnesyl diphosphate, the lipid donor molecule. All farnesyltransferase substrates have a cysteine as their fourth-to-last residue.

This gene is a member of the glycoprotein hormone beta chain family and encodes the beta subunit of luteinizing hormone (LH). Glycoprotein hormones are heterodimers consisting of a common alpha subunit and a unique beta subunit (this protein) which confers biological specificity. LH is expressed in the pituitary gland and promotes spermatogenesis and ovulation by stimulating the testes and ovaries to synthesize steroids.

First, chorismate is converted to anthranilate by the alpha-subunit of anthranilate synthase (ASA). Anthranilate reacts with 5-phosphoribose pyrrophosphate to produce 5-phosphoribosylanthranilate. Then this intermediate is converted to indole glycerol phosphate, which interacts with the alpha-subunit of tryptophan (TSA) synthase to yield indole. The beta-subunit of tryptophan synthase (TSB) catalyzes condensation of indole with serine, leading to tryptophan.

DNA-directed RNA polymerase II subunit RPB7 is an enzyme that in humans is encoded by the POLR2G gene. This gene encodes the seventh largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. In yeast, the association of this subunit with the polymerase under suboptimal growth conditions indicates it may play a role in regulating polymerase function.

An intriguing feature of gustducin is its similarity to transducin. These two G proteins have been shown to be structurally and functionally similar, leading researchers to believe that the sense of taste evolved in a similar fashion to the sense of sight. Gustducin is a heterotrimeric protein composed of the products of the GNAT3 (α-subunit), GNB1 (β-subunit) and GNG13 (γ-subunit).

60S acidic ribosomal protein P0 is a protein that in humans is encoded by the RPLP0 gene. Ribosomes catalyze protein synthesis and consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

Four different regulatory subunits and three catalytic subunits of PKA have been identified in humans. The protein encoded by this gene is one of the regulatory subunits. This subunit can be phosphorylated by the activated catalytic subunit. This subunit has been shown to interact with and suppress the transcriptional activity of the cAMP responsive element binding protein 1 (CREB1) in activated T cells.

40S ribosomal protein S4, X isoform is a protein that in humans is encoded by the RPS4X gene. Ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes ribosomal protein S4, a component of the 40S subunit.

Glutamate-cysteine ligase regulatory subunit is an enzyme that in humans is encoded by the GCLM gene. Glutamate-cysteine ligase, also known as gamma- glutamylcysteine synthetase, is the first rate limiting enzyme of glutathione synthesis. The enzyme consists of two subunits, a heavy catalytic subunit and a light regulatory subunit. Gamma glutamylcysteine synthetase deficiency has been implicated in some forms of hemolytic anemia.

60S ribosomal protein L6 is a protein that in humans is encoded by the RPL6 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

60S ribosomal protein L32 is a protein that in humans is encoded by the RPL32 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S5 is a ribosomal subunit of the Eukaryotic ribosome (80S) complex. In humans it is encoded by the RPS5 gene. Ribosomes, the organelles that catalyze protein synthesis, in eukaryotes, consist of a small 40S subunit and a large 60S subunit (whereas prokaryotic ribosomes are 70 Svedberg units, composed of 50S and 30S subunits). They are located in the cytoplasm.

60S ribosomal protein L7a is a protein that in humans is encoded by the RPL7A gene. Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

40S ribosomal protein S3a is a protein that in humans is encoded by the RPS3A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

Bacterial initiation factor 1 associates with the 30S ribosomal subunit in the A site and prevents an aminoacyl-tRNA from entering. It modulates IF2 binding to the ribosome by increasing its affinity. It may also prevent the 50S subunit from binding, stopping the formation of the 70S subunit. It also contains a β-domain fold common for nucleic acid binding proteins.

This encoded protein is the V1 domain F subunit protein. Subunit F is a 16 kDa protein that is required for the assembly and activity of V-ATPase, and has a potential role in the differential targeting and regulation of the enzyme for specific organelles. This subunit is not necessary for the rotation of the ATPase V1 rotor, but it does promote catalysis.

40S ribosomal protein S16' is a protein that in humans is encoded by the RPS16 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

60S ribosomal protein L4 is a protein that in humans is encoded by the RPL4 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

DNA polymerase subunit gamma-2, mitochondrial is a protein that in humans is encoded by the POLG2 gene. The POLG2 gene encodes a 55 kDa accessory subunit protein that imparts high processivity and salt tolerance to the catalytic subunit of DNA polymerase gamma, encoded by the POLG gene. Mutations in this gene result in autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions.

GA-binding protein subunit beta-1 is a protein that in humans is encoded by the GABPB1 gene. This gene encodes the GA-binding protein transcription factor, beta subunit. This protein forms a tetrameric complex with the alpha subunit, and stimulates transcription of target genes. The encoded protein may be involved in activation of cytochrome oxidase expression and nuclear control of mitochondrial function.

60S ribosomal protein L18a is a protein that in humans is encoded by the RPL18A gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit.

The RPS2 gene is the gene which, in humans, encodes the 40S ribosomal protein S2. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S9 is a protein that in humans is encoded by the RPS9 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

40S ribosomal protein S14 is a protein that in humans is encoded by the RPS14 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

CCR4-NOT transcription complex subunit 6 like is a protein that in humans is encoded by the CNOT6L gene. It is a paralog of CNOT6 and therefore a potential subunit of the CCR4-Not deadenylase complex.

Rattlesnake presynaptic neurotoxins: primary structures and evolutionary origin of the acidic subunit. Biochemistry 24:7054-58. The basic subunit (a phospholipase A2) is mildly toxic and apparently rather common in North American rattlesnake venoms.Powell, R.L. 2003.

This nuclear gene encodes subunit VIc, which has 77% amino acid sequence identity with mouse COX subunit VIc. This gene is up-regulated in prostate cancer cells. A pseudogene COX6CP1 has been found on chromosomes 16p12.

Both subunit receptors are essential for IL-25 functions. IL-25 does not bind directly to IL-17RA, but this subunit is necessary for its functions - as well as IL-17RB which directly bind IL-25.

Acetylcholinesterase collagenic tail peptide also known as AChE Q subunit, acetylcholinesterase-associated collagen, or ColQ is the collagen-tail subunit of acetylcholinesterase found in the neuromuscular junction. In humans it is encoded by the COLQ gene.

Calcium channel, voltage-dependent, L type, alpha 1C subunit (also known as Cav1.2) is a protein that in humans is encoded by the CACNA1C gene. Cav1.2 is a subunit of L-type voltage-dependent calcium channel.

Mutations in the alpha or beta subunit genes lead to an accumulation of GM2 ganglioside in neurons and neurodegenerative disorders termed the GM2 gangliosidoses. Beta subunit gene mutations lead to Sandhoff disease (GM2-gangliosidosis type II).

Since the large ribosomal subunit is 28S (approximately 5kb) and the small ribosomal subunit is 18S (approximately 2kb) two prominent bands appear on the gel, the larger at close to twice the intensity of the smaller.

Ribbon diagram of shiga toxin (Stx) from Shigella dysenteriae, showing the characteristic AB5 structure. A subunit is in orange and B-subunit complex is in blue. From . There are four main families of the AB5 toxin.

Follitropin subunit beta also known as follicle-stimulating hormone beta subunit (FSH-B) is a protein that in humans is encoded by the FSHB gene. Alternative splicing results in two transcript variants encoding the same protein.

Class IA PI3Ks are composed of a heterodimer between a p110 catalytic subunit and a p85 regulatory subunit. There are five variants of the p85 regulatory subunit, designated p85α, p55α, p50α, p85β, and p55γ. There are also three variants of the p110 catalytic subunit designated p110α, β, or δ catalytic subunit. The first three regulatory subunits are all splice variants of the same gene (Pik3r1), the other two being expressed by other genes (Pik3r2 and Pik3r3, p85β, and p55γ, respectively). The most highly expressed regulatory subunit is p85α; all three catalytic subunits are expressed by separate genes (Pik3ca, Pik3cb, and Pik3cd for p110α, p110β, and p110δ, respectively). The first two p110 isoforms (α and β) are expressed in all cells, but p110δ is expressed primarily in leukocytes, and it has been suggested that it evolved in parallel with the adaptive immune system.

Transcription initiation factor TFIID subunit 1, also known as transcription initiation factor TFIID 250 kDa subunit (TAFII-250) or TBP-associated factor 250 kDa (p250), is a protein that in humans is encoded by the TAF1 gene.

Mediator of RNA polymerase II transcription subunit 30 is an enzyme that in humans is encoded by the MED30 gene. It represents subunit Med30 of the Mediator complex and is metazoan-specific, having no homologues in yeasts.

Neuronal acetylcholine receptor subunit alpha-5, also known as nAChRα5, is a protein that in humans is encoded by the CHRNA5 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR).

Neuronal acetylcholine receptor subunit alpha-2, also known as nAChRα2, is a protein that in humans is encoded by the CHRNA2 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR).

Neuronal acetylcholine receptor subunit alpha-7, also known as nAChRα7, is a protein that in humans is encoded by the CHRNA7 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR).

PFOR adopts a dimeric structure, while each monomeric subunit is composed of one or multiple chain(s) of polypeptides. Each monomeric subunit of PFOR consists of six domains binding one TPP molecule and three [4Fe-4S] clusters.

Knockout studies in mice suggest that this subunit may play an important role in regulating energy balance and adiposity. The studies also suggest that this subunit may mediate the gene induction and cataleptic behavior induced by haloperidol.

This gene encodes a small subunit associated with a subset of TFIID complexes. This subunit interacts with TBP and with two other small subunits of TFIID, TAF10 and TAF11. There is a pseudogene located on chromosome 6.

Interleukin 27 receptor, alpha subunit has been shown to interact with STAT1.

This unit started as a subunit of the Winburg Commando around 1900.

An essential cofactor for ADCY2 is magnesium; two ions bind per subunit.

BRCA1 interacts with the NELF-B (COBRA1) subunit of the NELF complex.

The structure is reminiscent of the Mo6S8 subunit of the Chevrel phases.

This family is related to single- subunit reverse transcriptase and DNA polymerase.

SdhE interacts with the catalytic subunit of the succinate dehydrogenase (SDH) complex.

This gene encodes an alpha isoform of the constant regulatory subunit A.

This gene encodes an alpha isoform of the regulatory subunit B56 subfamily.

This gene encodes an alpha isoform of the regulatory subunit B55 subfamily.

This gene encodes a beta isoform of the regulatory subunit B56 subfamily.

Three alternatively spliced transcript variants encode two isoforms of the H subunit.

This gene encodes an epsilon isoform of the regulatory subunit B56 subfamily.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 11, mitochondrial (NADH-ubiquinone oxidoreductase ESSS subunit) is an enzyme that in humans is encoded by the NDUFB11 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 11 is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain. NDUFB11 mutations have been associated with linear skin defects with multiple congenital anomalies 3 and mitochondrial complex I deficiency.

Gamma-aminobutyric acid receptor subunit pi is a protein that in humans is encoded by the GABRP gene. The gamma-aminobutyric acid (GABA) A receptor is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. The subunit encoded by this gene is expressed in several non-neuronal tissues including the uterus and ovaries. This subunit can assemble with known GABA A receptor subunits, and the presence of this subunit alters the sensitivity of recombinant receptors to modulatory agents such as pregnanolone.

DNA-directed RNA polymerase III subunit RPC10 is an enzyme that in humans is encoded by the POLR3K gene. This gene encodes a small essential subunit of RNA polymerase III, the polymerase responsible for synthesizing transfer and small ribosomal RNAs in eukaryotes. The carboxy-terminal domain of this subunit shares a high degree of sequence similarity to the carboxy-terminal domain of an RNA polymerase II elongation factor. This similarity in sequence is supported by functional studies showing that this subunit is required for proper pausing and termination during transcription.

SCS, also known as succinyl CoA ligase (SUCL), is a heterodimer composed of a catalytic α subunit encoded by the SUCLG1 gene and a β subunit encoded by either the SUCLA2 gene or the SUCLG2 gene, which determines the enzyme specificity for either ADP or GDP. SUCLA2 is the SCS variant containing the SUCLA2-encoded β subunit. Amino acid sequence alignment of the two β subunit types reveals a homology of ~50% identity, with specific regions conserved throughout the sequences. SUCLA2 is located on chromosome 13 and contains 13 exons.

SCS, also known as succinyl CoA ligase (SUCL), is a heterodimer composed of a catalytic α subunit encoded by the SUCLG1 gene and a β subunit encoded by either the SUCLA2 gene or the SUCLG2 gene, which determines the enzyme specificity for either ADP or GDP. SUCLG2 is the SCS variant containing the SUCLG2-encoded β subunit. Amino acid sequence alignment of the two β subunit types reveals a homology of ~50% identity, with specific regions conserved throughout the sequences. SUCLG2 is located on chromosome 3 and contains 14 exons.

Rotation of the central stalk against the surrounding alpha3beta3 subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (By similarity). The epsilon subunit is located in the stalk region of the F1 complex, and acts as an inhibitor of the ATPase catalytic core. The epsilon subunit can assume two conformations, contracted and extended, where the latter inhibits ATP hydrolysis. The conformation of the epsilon subunit is determined by the direction of rotation of the gamma subunit, and possibly by the presence of ADP.

Volkensin is a eukaryotic ribosome-inactivating protein found in the Adenia volkensii plant. It is a glycoprotein with two subunits A and B. A subunit is linked to B subunit with disulfide bridges and non-covalent bonds. B subunit is responsible for binding to the galactosyl-terminated receptors on the cell membrane that allows the entry the A subunit of the toxin into the cell, which performs the inhibitory function. Volkensin is a galactose specific lectin that can inhibit protein synthesis in whole cells and in cell-free lysates.

The Gγ subunit is considerably smaller than Gβ, and is unstable on its own, requiring interaction with Gβ to fold, explaining the close association of the dimer. In the Gβγ dimer, the Gγ subunit wraps around the outside of Gβ, interacting through hydrophobic associations, and exhibits no tertiary interactions with itself. The N terminus helical domains of the two subunits form a coiled coil with one another that typically extends away from the core of the dimer. To date, 5 β-subunit and 11 γ-subunit genes and have been identified in mammals.

To fully reduce the quinone in SQR, two electrons as well as two protons are needed. It has been argued that a water molecule (HOH39) arrives at the active site and is coordinated by His207 of subunit B, Arg31 of subunit C, and Asp82 of subunit D. The semiquinone species is protonated by protons delivered from HOH39, completing the ubiquinone reduction to ubiquinol. His207 and Asp82 most likely facilitate this process. Other studies claim that Tyr83 of subunit D is coordinated to a nearby histidine as well as the O1 carbonyl oxygen of ubiquinone.

The β-tubulin subunit is exposed on the plus end of the microtubule while the α-tubulin subunit is exposed on the minus end. After the dimer is incorporated into the microtubule, the molecule of GTP bound to the β-tubulin subunit eventually hydrolyzes into GDP through inter-dimer contacts along the microtubule protofilament. The GTP molecule bound to the α-tubulin subunit is not hydrolyzed during the whole process. Whether the β-tubulin member of the tubulin dimer is bound to GTP or GDP influences the stability of the dimer in the microtubule.

MUC-4 is an O-glycoprotein that can reach up to 2 micrometers outside the cell. MUC-4 mucins consist of a large extracellular alpha subunit that is heavily glycosylated and a beta subunit that is anchored in the cell membrane and extends into the cytosol. This beta subunit is considered an oncogene, whose role in cancer is increasingly being recognized particularly due to its involvement in signalling pathways, particularly with ErbB2 (Her2). This subunit serves as a ligand for ErbB2, which is suggested to cause the repression of apoptosis found in many cancer cells.

Serine/threonine-protein phosphatase 2A 55 kDa regulatory subunit B beta isoform is an enzyme that in humans is encoded by the PPP2R2B gene. The product of this gene belongs to the phosphatase 2regulatory subunit B family. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits.

This particular subunit has been shown to interact specifically with the hepatitis B virus X protein, a protein critical to viral replication. In addition, this subunit is involved in regulating hepatitis virus C internal ribosome entry site (IRES) activity, an activity essential for viral replication. This core alpha subunit is also involved in regulating the hypoxia-inducible factor-1alpha, a transcription factor important for cellular responses to oxygen tension. Recent study on underlying mechanisms of E3 ligase Parkin-related neurodegeneration identified this proteasome subunit as one of Parkin associating partner.

N-alpha-acetyltransferase 10 (NAA10) also known as NatA catalytic subunit Naa10 and arrest-defective protein 1 homolog A (ARD1A) is an enzyme subunit that in humans is encoded NAA10 gene. Together with its auxiliary subunit Naa15, Naa10 constitutes the NatA (Nα-acetyltransferase A) complex that specifically catalyzes the transfer of an acetyl group from acetyl-CoA to the N-terminal primary amino group of certain proteins. In higher eukaryotes, 5 other N-acetyltransferase (NAT) complexes, NatB-NatF, have been described that differ both in substrate specificity and subunit composition.

The function of the essential Esa1 protein as the HAT subunit of NuA4 and the presence of Tra1p, a putative transcription activator-interacting subunit, supports an essential link between nuclear H4 acetylation, transcriptional regulation and cell cycle control.

Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein, which shares sequence similarity with yeast ribosomal protein L44, belongs to the L44E (L36AE) family of ribosomal proteins.

This gene encodes the largest subunit of TFIID. This subunit binds to core promoter sequences encompassing the transcription start site. It also binds to activators and other transcriptional regulators, and these interactions affect the rate of transcription initiation. This subunit contains two independent protein kinase domains at the N and C-terminals, but also possesses acetyltransferase activity and can act as a ubiquitin-activating/conjugating enzyme.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 10 is an enzyme that in humans is encoded by the NDUFB10 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 10 is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 9 is an enzyme that in humans is encoded by the NDUFB9 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 9 is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain.

Guanine nucleotide-binding protein G(olf) subunit alpha is a protein that in humans is encoded by the GNAL gene. Its main product is the heterotrimeric G-protein alpha subunit Golf-α, a member of the Gs alpha subunit family that is a key component of G protein-coupled receptor-regulated adenylyl cyclase signal transduction pathways in the olfactory system and the striatum in the brain.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 8, mitochondrial is an enzyme that in humans is encoded by the NDUFB8 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 8 is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain.

NAD(+)-dependent isocitrate dehydrogenases catalyze the allosterically regulated rate-limiting step of the tricarboxylic acid cycle. Each isozyme is a heterotetramer that is composed of two alpha subunits, one beta subunit, and one gamma subunit. The protein encoded by this gene is the beta subunit of one isozyme of NAD(+)-dependent isocitrate dehydrogenase. Three alternatively spliced transcript variants encoding different isoforms have been described for this gene.

Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-3 is a protein that in humans is encoded by the GNB3 gene. Heterotrimeric guanine nucleotide- binding proteins ( G proteins), which integrate signals between receptors and effector proteins, are composed of an alpha, a beta, and a gamma subunit. These subunits are encoded by families of related genes. This gene encodes a beta subunit.

The CHRNE gene codes for the epsilon subunit of the AChR. Most mutations are autosomal recessive loss-of-function mutations and as a result there is endplate AChR deficiency. CHRNE is associated with changing the kinetic properties of the AChR. One type of mutation of the epsilon subunit of the AChR introduces an Arginine into the binding site at the α/ε subunit interface of the receptor.

The ATPase F1 complex gamma subunit forms the central shaft that connects the Fo rotary motor to the F1 catalytic core. The gamma subunit functions as a rotary motor inside the cylinder formed by the alpha(3)beta(3) subunits in the F1 complex. The best-conserved region of the gamma subunit is its C-terminus, which seems to be essential for assembly and catalysis.

Calcium-activated potassium channel subunit beta-2 comprises two domains. An N-terminal cytoplasmic domain, the ball and chain domain, which is responsible for the fast inactivation of these channels, and a C-terminal calcium-activated potassium channel beta subunit domain. The N-terminal domain only occurs in calcium-activated potassium channel subunit beta-2, while the C-terminal domain is found in related proteins.

40S ribosomal protein S7 is a protein that in humans is encoded by the RPS7 gene. In eukaryotes, ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit.

Mitochondrial-processing peptidase (MPP) is a metalloendopeptidase, containing two structurally related subunits, mitochondrial-processing peptidase subunit alpha and subunit beta, working in conjunction for its catalytic function. Containing the catalytic site, the beta subunit PMPCB protein cleaves presequences (transit peptides) from mitochondrial protein precursors and releases of N-terminal transit peptides from precursor proteins imported into the mitochondrion, typically with Arg in position P2.

Mitochondrial-processing peptidase (MPP) is a metalloendopeptidase, containing two structurally related subunits, Subunit alpha and mitochondrial-processing peptidase subunit beta, working in conjunction for its catalytic function. Containing the catalytic site, the beta subunit PMPCB protein cleaves presequences (transit peptides) from mitochondrial protein precursors and releases of N-terminal transit peptides from precursor proteins imported into the mitochondrion, typically with Arg in position P2.

There are at least six types of GEFS+, delineated by their causative gene. Known causative genes are the sodium channel α subunit genes SCN1A, an associated β subunit SCN1B, and a GABAA receptor γ subunit gene, GABRG2 and there is another gene related with calcium channel the PCDH19 which is also known as Epilepsy Female with Mental Retardation. Penetrance for this disorder is estimated at approximately 60%.

The regulatory subunit p85 binds to phosphorylated tyrosine residues on the activated receptor via its Src homology 2 (SH2) domain. It then recruits the catalytic subunit p110 to form the fully active PI3K enzyme. Alternatively, adaptor molecule Grb2 binds to phospho-YXN motifs of the RTK and recruits p85 via Grb2-associated binding (GAB) scaffold protein. The p110 subunit can also be recruited independently of p85.

Subunit d in V-ATPases, called subunit C in A-ATpases, is a part of the Vo complex. They fit onto the middle of the c ring, so are thought to function as a rotor. There are two versions of this subunit in eukaryotes, d/d1 and d2. In mammals, d1 (ATP6V0D1) is the ubiquitously expressed version and d2 (ATP6V0D2) is expressed in specific cell types only.

There are seven subunits within the α1 subunit. The A subunit, called α1ACa2+, corresponds to what is functionally defined as the P-type and Q-type isoforms. P-type and Q-type calcium channels are closely related as they are produced from the same gene via alternative splicing. As a complication of the alternative splicing, P-type and Q-type channels may have different subunit compositions.

This complex is implicated in the binding of transfer RNA to messenger RNA (mRNA). The small subunit is responsible for the binding and the reading of the mRNA during translation. The small subunit, both the rRNA and its proteins, complexes with the large 50S subunit to form the 70S prokaryotic ribosome in prokaryotic cells. This 70S ribosome is then used to translate mRNA into proteins.

Proteasome subunit alpha type-4 also known as macropain subunit C9, proteasome component C9, and 20S proteasome subunit alpha-3 is a protein that in humans is encoded by the PSMA4 gene. This protein is one of the 17 essential subunits (alpha subunits 1–7, constitutive beta subunits 1–7, and inducible subunits including beta1i, beta2i, beta5i) that contributes to the complete assembly of 20S proteasome complex.

Phosphorylation of the GABAA by cAMP-dependent protein kinase (PKA) has a regulatory effect dependent on the beta subunit involved. The mechanism by which the kinase is targeted towards the bata-3 subunit is unknown. AKAP79/150 binds directly to the GABRB3 subunit, which is critical for its own phosphorylation, mediated by PKA. Gabrb3 shows significantly reduced expression postnatally, when mice are deficient in MECP2.

5'-AMP-activated protein kinase subunit beta-1 is an enzyme that in humans is encoded by the PRKAB1 gene. The protein encoded by this gene is a regulatory subunit of the AMP-activated protein kinase (AMPK). AMPK is a heterotrimer consisting of an alpha catalytic subunit, and non-catalytic beta and gamma subunits. AMPK is an important energy-sensing enzyme that monitors cellular energy status.

Ribosomes, the complexes that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. The RPL3 gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L3P family of ribosomal proteins and it is located in the cytoplasm.

60S acidic ribosomal protein P2 is a protein that in humans is encoded by the RPLP2 gene. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal phosphoprotein that is a component of the 60S subunit.

Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-2 is a protein that in humans is encoded by the GNB2 gene. Heterotrimeric guanine nucleotide- binding proteins (G proteins), which integrate signals between receptors and effector proteins, are composed of an alpha, a beta, and a gamma subunit. These subunits are encoded by families of related genes. This gene encodes a beta subunit.

Guanine nucleotide-binding protein G(t) subunit alpha-1 is a protein that in humans is encoded by the GNAT1 gene. Transducin is a 3-subunit guanine nucleotide-binding protein (G protein) which stimulates the coupling of rhodopsin and cGMP-phosphodiesterase during visual impulses. The transducin alpha subunits in rods and cones are encoded by separate genes. This gene encodes the alpha subunit in rods.

Interleukin 11 receptor, alpha subunit is a subunit of the interleukin 11 receptor. IL11RA is its human gene. Interleukin 11 is a stromal cell-derived cytokine that belongs to a family of pleiotropic and redundant cytokines that use the gp130 transducing subunit in their high affinity receptors. This gene encodes the IL-11 receptor, which is a member of the hematopoietic cytokine receptor family.

40S ribosomal protein S4, Y isoform 1 is a protein that in humans is encoded by the RPS4Y1 gene. Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes ribosomal protein S4, a component of the 40S subunit.

5'-AMP-activated protein kinase subunit beta-2 is an enzyme that in humans is encoded by the PRKAB2 gene. The protein encoded by this gene is a regulatory subunit of the AMP-activated protein kinase (AMPK). AMPK is a heterotrimer consisting of an alpha catalytic subunit, and non-catalytic beta and gamma subunits. AMPK is an important energy-sensing enzyme that monitors cellular energy status.

Phosphatidylinositol 3-kinase phosphorylates the inositol ring of phosphatidylinositol at the 3-prime position. The enzyme comprises a 110 kD catalytic subunit and a regulatory subunit of either 85, 55, or 50 kD. This gene encodes the 85 kD regulatory subunit. Phosphatidylinositol 3-kinase plays an important role in the metabolic actions of insulin, and a mutation in this gene has been associated with insulin resistance.

Eukaryotic ribosome. The 40S subunit is on the left, the 60S subunit on the right. The ribosomal RNA (rRNA) core is represented as a grey tube, expansion segments are shown in red. Universally conserved proteins are shown in blue.

This gene encodes the subunit s, also known as factor B, of the proton channel. This subunit is necessary for the energy transduction activity of the ATP synthase complexes. Alternatively spliced transcript variants encoding different isoforms have been identified.

5S rRNA is transcribed by RNA polymerase III. The 18S rRNA in most eukaryotes is in the small ribosomal subunit, and the large subunit contains three rRNA species (the 5S, 5.8S and 28S in mammals, 25S in plants, rRNAs).

Within the paraphyletic Neoplecostominae, Pareiorhina forms a monophyletic subunit that also includes Neoplecostomus.

Interleukin 5 has been shown to interact with Interleukin 5 receptor alpha subunit.

These typical complexes also contain a third type of subunit, the γ chain.

The ATP5MF gene encodes the ATP synthase subunit f, mitochondrial enzyme in humans.

This encoded protein is known as the D subunit and is found ubiquitously.

This subunit is one of the gamma regulatory subunits of AMPK. It is dominantly expressed in skeletal muscle. Studies of the pig counterpart suggest that this subunit may play a key role in the regulation of energy metabolism in skeletal muscle.

It is possible that the p41 subunit is involved in assembling and maintaining the structure of the Arp2/3 complex. Multiple versions of the p41 subunit may adapt the functions of the complex to different cell types or developmental stages.

This nuclear gene encodes polypeptide 1 (muscle isoform) of subunit VIIa and the polypeptide 1 is present only in muscle tissues. Other polypeptides of subunit VIIa are present in both muscle and nonmuscle tissues, and are encoded by different genes.

The regulatory subunits interact with the catalytic subunit through a conserved RVXF motif (Egloff et al., 1997). When this binding site is deleted from regulatory proteins, they lose the ability to associate with the catalytic subunit (Egloff et al., 1997).

In the base sub complex, Rpn1 offers a docking position for subunit Rpn10 at its central solenoid portion, although such association with Rpn10 is stabilized by a third subunit, Rpn2. Rpn10 serve as a receptor for poly-ubiquitylated protein substrates.

Mediator of RNA polymerase II transcription subunit 1 also known as DRIP205 or Trap220 is a subunit of the Mediator complex and is a protein that in humans is encoded by the MED1 gene. MED1 functions as a nuclear receptor coactivator.

Interleukin 10 receptor, beta subunit is a subunit for the interleukin-10 receptor. IL10RB is its human gene. IL10RB has also recently been designated CDW210B (cluster of differentiation W210B). The protein encoded by this gene belongs to the cytokine receptor family.

Although the Na,K-ATPase does not depend on the gamma subunit to be functional, it is thought that the gamma subunit modulates the enzyme's activity by inducing ion channel activity. Mutations in this gene have been associated with renal hypomagnesaemia.

POLG2 encodes the processivity subunit of the mitochondrial DNA polymerase gamma. The encoded protein forms a heterotrimer containing one catalytic subunit and two processivity subunits. This protein enhances DNA binding, stimulates polymerase and exonuclease activity, and promotes processive DNA synthesis.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 7, also known as complex I-B18, is an enzyme that in humans is encoded by the NDUFB7 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 7 is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain.

2004 48: 1307-1312 They compete with ATP for binding to the B subunit of this enzyme and inhibit the ATP-dependent DNA supercoiling catalysed by gyrase. X-ray crystallography studies have confirmed binding at the ATP-binding site located on the gyrB subunit of DNA gyrase. Their affinity for gyrase is considerably higher than that of modern fluoroquinolones, which also target DNA gyrase but at the gyrA subunit.

Acetylcholine receptor subunit beta is a protein that in humans is encoded by the CHRNB1 gene. The muscle acetylcholine receptor is composed of five subunits: two alpha subunits and one beta, one gamma, and one delta subunit. This gene encodes the beta subunit of the acetylcholine receptor. The acetylcholine receptor changes conformation upon acetylcholine binding leading to the opening of an ion-conducting channel across the plasma membrane.

NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 6, also known as complex I-B17, is a protein that in humans is encoded by the NDUFB6 gene. NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 6, is an accessory subunit of the NADH dehydrogenase (ubiquinone) complex, located in the mitochondrial inner membrane. It is also known as Complex I and is the largest of the five complexes of the electron transport chain.

ATP synthase subunit s, mitochondrial is an enzyme that in humans is encoded by the ATP5S gene. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of two linked multi-subunit complexes: the soluble catalytic core, F1, and the membrane-spanning component, Fo, comprising the proton channel.

Marshall NF, Price DH. Purification of P-TEFb, a transcription factor required for the transition into productive elongation. J Biol Chem 1995; 270:12335-8. It is a cyclin dependent kinase containing the catalytic subunit, Cdk9, and a regulatory subunit, cyclin T in Drosophila.Peng J, Marshall NF, Price DH. Identification of a cyclin subunit required for the function of Drosophila P-TEFb. J Biol Chem 1998; 273:13855-60.

Similar to other caspases, caspase-9 has three domains: N-terminal pro-domain, large subunit, and a small subunit. The N-terminal pro-domain is also called the long pro-domain and this contains the caspase activation domain (CARD) motif. The pro-domain is linked to the catalytic domain by a linker loop. The caspase-9 monomer consists of one large and one small subunit, both comprising the catalytic domain.

The human ATP5F1C gene encodes the gamma subunit of an enzyme called mitochondrial ATP synthase. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes adenosine triphosphate (ATP) synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of two linked multi-subunit complexes: the soluble catalytic core, F1, and the membrane-spanning component, F0, comprising the proton channel.

ATP synthase subunit b, mitochondrial is an enzyme that in humans is encoded by the ATP5PB gene. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of two linked multi-subunit complexes: the soluble catalytic core, F1, and the membrane-spanning component, Fo, comprising the proton channel.

The open subunit is the configuration most crucial to the putative substrate-binding cleft, as it is where the target peptide can access the active center. The closed subunit blocks this target peptide because of a neighboring unwound alpha helix. Additionally, the ATP-binding loop in one PDK3 subunit adopts an open conformation, implying that the nucleotide loading into the active site is mediated by the inactive "pre-insertion" binding mode.

BK channels are formed by α subunits and accessory β subunits arranged in tetramers. The α subunit forms the ion conduction pore and the β subunit contributes to channel gating. IPA interaction with the BK channel enhances Ca2+ and / or voltage sensitivity of the α subunit of BK channels without affecting the channel conductance. In this state BK channels can still be inhibited by one of their inhibitors, like charybdotoxin (CTX).

The interleukin-5 receptor is a type I cytokine receptor. It is a heterodimer of the interleukin 5 receptor alpha subunit and CSF2RB. The IL-5 receptor (IL-5R) belongs to the type I cytokine receptor family and is a heterodimer composed of two polypeptide chains, one α subunit, which binds IL-5 and confers upon the receptor cytokine specificity, and one β subunit, which contains the signal transduction domains.

Rab3 GTPase-activating protein non-catalytic subunit is an enzyme that in humans is encoded by the RAB3GAP2 gene. Members of the RAB3 protein family (see RAB3A; MIM 179490) are implicated in Ca(2+)-dependent exocytosis. RAB3GAP, which is involved in regulation of RAB3 activity, is a heterodimeric complex consisting a 130-kD catalytic subunit (RAB3GAP1; MIM 602536) and a 150-kD noncatalytic subunit (RAB3GAP2) (Nagano et al., 1998).

Interleukin-23 subunit alpha is a protein that in humans is encoded by the IL23A gene. IL-23 is produced by dendritic cells and macrophages. Interleukin-23 is a heterodimeric cytokine composed of an IL-12p40 subunit that is shared with IL-12 and the IL-23p19 subunit. A functional receptor for IL-23 (the IL-23 receptor) has been identified and is composed of IL-12R β1 and IL-23R.

Shwachman–Diamond syndrome (SDS) is caused by bi-allelic mutations in the SBDS protein that affects its ability to couple GTP hydrolysis by the GTPase EFL1 to the release of eIF6 from the 60S subunit. Clinically, SDS affects multiple systems, causing bony abnormalities, and pancreatic and neurocognitive dysfunction. SBDS associates with the 60S subunit in human cells and has a role in subunit joining and translational activation in yeast models.

A leukocidin is a type of cytotoxin created by some types of bacteria (Staphylococcus). It is a type of pore-forming toxin. The model for pore formation is step-wise. First, the cytotoxin’s “S” subunit recognizes specific protein-containing receptors, or an integrin on the host cell’s surface. The S subunit then recruits a second, “F” subunit, and the two subunits dimerize on the surface of the host’s cell.

Generalized epilepsy with febrile seizures plus (GEFS+) is an umbrella for many other syndromes that share causative genes. Patients experience febrile seizures early in childhood and grow to experience other types of seizures later in life. Known causative genes for GEFS+ are the sodium channel α subunit genes SCN1A and SCN2A and the β subunit gene SCN1B. Mutations in the GABAA receptor γ subunit GABRG1 are also causative for this disorder.

These interactions along with the association of the small and large ribosomal subunits result in a functioning ribosome capable of synthesizing proteins. An example of a fully-assembled small subunit of ribosomal RNA in prokaryotes, specifically Thermus Thermophilus. The actual ribosomal RNA (16S) is shown coiled in orange with ribosomal proteins attaching in blue. Ribosomal RNA organizes into two ribosomal subunits: the large ribosomal subunit (LSU) and small ribosomal subunit (SSU).

The A subunit of an AB5 toxin is the portion responsible for catalysis of specific targets. For Shiga toxin family, the A subunit hosts a Trypsin-sensitive region which gives out two fragmented domains when cleaved. This region has not been confirmed for the other AB5 toxin families as yet. In general, the two domains of the A subunit, named A1 and A2, are linked by a disulfide bond.

Protein farnesyltransferase/geranylgeranyltransferase type-1 subunit alpha is an enzyme that in humans is encoded by the FNTA gene. Prenyltransferases attach either a farnesyl group or a geranylgeranyl group in thioether linkage to the cysteine residue of protein's with a C-terminal CAAX box. CAAX geranylgeranyltransferase and CAAX farnesyltransferase are heterodimers that share the same alpha subunit but have different beta subunits. This gene encodes the alpha subunit of these transferases.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal phosphoprotein that is a component of the 60S subunit. The protein, which is a functional equivalent of the Escherichia coli L7/L12 ribosomal protein, belongs to the L12P family of ribosomal proteins.

This gene encodes a small subunit of TFIID that is present in all TFIID complexes and interacts with TBP. This subunit also interacts with another small subunit, TAF13, to form a heterodimer with a structure similar to the histone core structure. In molecular biology, TAFII28 refers to the TATA box binding protein associated factor. Together with the TATA-binding protein and other TAFs it forms the general transcription factor, TFIID.

NR2 subunit in vertebrates (left) and invertebrates (right). Ryan et al., 2008 While a single GluN2 subunit is found in invertebrate organisms, four distinct isoforms of the GluN2 subunit are expressed in vertebrates and are referred to with the nomenclature GluN2A through GluN2D (encoded by GRIN2A, GRIN2B, GRIN2C, GRIN2D). Strong evidence shows that the genes encoding the GluN2 subunits in vertebrates have undergone at least two rounds of gene duplication.

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit, where it forms part of the domain where translation is initiated. The protein belongs to the S3P family of ribosomal proteins.

The C-terminus of each small subunit is inserted into a large subunit to form the active site. In the enzyme's activated form the C-terminus is present as a thiocarboxylate, which acts as the sulfur donor to precursor Z in MoCo biosynthesis. As a result, the active site of the enzyme must be in close proximity to the C-terminus of the small subunit (i.e. MoaD in prokaryotes).

Splicing factor 3B, 14 kDa subunit, also known as SF3B14, is a human gene.

HAUS augmin like complex subunit 6, also known as HAUS6, is a human gene.

In addition, the Gα subunit activates Src-dependent integrin signaling which can activate PI3K.

ICP34.5 shares the C-terminal regulatory domain () with protein phosphatase 1 subunit 15A/B.

Tandem repeats of the eukaryotic rDNA gene cluster containing the genetic sequences for the 18S, 5.8S, and 28S subunits of the ribosome. ETS – external transcribed spacer, ITS – internal transcribed spacers 1 and 2, numbered from 5' end; NTS – nontranscribed spacer. In fungi, the Internal transcribed spacer (ITS) is a roughly 600 base pairs long region in the ribosomal tandem repeat gene cluster of the nuclear genome. The region is flanked by the DNA sequences for the ribosomal small subunit (SSU) or 18S subunit at the 5‘ end, and by the large subunit (LSU) or 28S subunit at the 3‘ end.

Protein phosphatase 2 (formerly named type 2A) is one of the four major Ser/Thr phosphatases and is implicated in the negative control of cell growth and division. Protein phosphatase 2 holoenzymes are heterotrimeric proteins composed of a structural subunit A, a catalytic subunit C, and a regulatory subunit B. The regulatory subunit is encoded by a diverse set of genes that have been grouped into the B/PR55, B'/PR61, and B/PR72 families. These different regulatory subunits confer distinct enzymatic specificities and intracellular localizations to the holozenzyme. The product of this gene belongs to the B family.

Some research suggests that this chronic desensitization is due to the over activation of a kinase, G protein-coupled receptor kinase 2 (GRK2), which phosphorylates and deactivates certain G protein coupled receptors . When the G protein coupled receptor is activated, the Gβγ subunit recruits GRK2 which then phosphorylates and desensitizes GPCRs like the βAR. Preventing the interaction of the βγ subunit with GRK2 has therefore been studied as a potential target for increasing heart contractile function. The developed molecule GRK2ct is a protein inhibitor which inhibits the signalling properties of Gβγ subunit but does not interfere with alpha subunit signalling.

Voltage gated P-type calcium channels consist of a main pore-forming α1 subunit (which is more specifically referred to as CaV2.1), an α2 subunit and a β subunit. There can be γ subunits found in calcium channels of skeletal muscles. The α1 subunit is encoded specifically by the CACNA1A gene and is composed of four domains, each containing six transmembrane (S1-S6) spanning α helices. The S1-S2 loop and the S6 region are thought to be responsible for the channel's inactivation, the S4 region serves as the voltage sensor and S5-S6 loop forms the pore.

Strychnine-sensitive GlyRs are members of a family of ligand-gated ion channels. Receptors of this family are arranged as five subunits surrounding a central pore, with each subunit composed of four α helical transmembrane segments. There are presently four known isoforms of the ligand-binding α-subunit (α1-4) of GlyR (GLRA1, GLRA2, GLRA3, GLRA4) and a single β-subunit (GLRB). The adult form of the GlyR is the heteromeric α1β receptor, which is believed to have a stoichiometry (proportion) of three α1 subunits and two β subunits or four α1 subunits and one β subunit.

The protein encoded by this gene is one subunit of a trimeric complex NF-Y, forming a highly conserved transcription factor that binds to CCAAT motifs in the promoter regions in a variety of genes. Subunit NFYA associates with a tight dimer composed of the NFYB and NFYC subunits, resulting in a trimer that binds to DNA with high specificity and affinity. The sequence specific interactions of the complex are made by the NFYA subunit, suggesting a role as the regulatory subunit. In addition, there is evidence of post-transcriptional regulation in this gene product, either by protein degradation or control of translation.

The gene PSMB7 encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit in the proteasome. Expression of this catalytic subunit (beta 2, according to systematic nomenclature) is downregulated by gamma interferon due to an alternatively elevated expression of inducible subunit beta2i, which leads to augmented incorporation of beta2i instead of beta2 into the final assembled 20S complex. The human protein proteasome subunit beta type-7 is 25 kDa in size and composed of 234 amino acids. The calculated theoretical pI of this protein is 5.61.

AP-3 complex subunit mu-1 is a protein that in humans is encoded by the AP3M1 gene. The protein encoded by this gene is the medium subunit of AP-3, which is an adaptor-related protein complex associated with the Golgi region as well as more peripheral intracellular structures. AP-3 facilitates the budding of vesicles from the Golgi membrane and may be directly involved in protein sorting to the endosomal/lysosomal system. AP-3 is a heterotetrameric protein complex composed of two large subunits (delta and beta3), a medium subunit (mu3), and a small subunit (sigma 3).

Evolutionary Genetics of Mojave Toxin Among Selected Rattlesnake Species (Squamata: Crotalinae). Unpublished PhD dissertation. El Paso: University of Texas. The less common acidic subunit is not toxic by itself, but in combination with the basic subunit, produces the potent neurotoxin called "Mojave toxin".

Interleukin-10 receptor is a type II cytokine receptor. The receptor is tetrameric, composed of 2α and 2β subunits. The α subunit is expressed on haematopoietic cells (such as T, B, NK, mast, and dendritic cells) whilst the β subunit is expressed ubiquitously.

The ATPAF2 gene encodes an essential housekeeping protein, an assembly factor for the F1 component of mitochondrial ATP synthase. This protein binds specifically to the F1 alpha subunit and is thought to prevent this subunit from forming nonproductive homooligomers during enzyme assembly.

Small subunit ribosomal ribonucleic acid (SSU rRNA) is the smallest of the two major RNA components of the ribosome. Associated with a number of ribosomal proteins, the SSU rRNA forms the small subunit of the ribosome. It is encoded by the SSU-rDNA.

In signal transduction via G protein, palmitoylation of the α subunit, prenylation of the γ subunit, and myristoylation is involved in tethering the G protein to the inner surface of the plasma membrane so that the G protein can interact with its receptor.

Gamma-aminobutyric acid receptor subunit gamma-1 is a protein that in humans is encoded by the GABRG1 gene. The protein encoded by this gene is a subunit of the GABAA receptor. Variants of this gene may be associated with alcohol dependence.

The B regulatory subunit might modulate substrate selectivity and catalytic activity. This gene encodes a beta isoform of the regulatory subunit B55 subfamily. Defects in the 5' UTR of this gene may cause a rare form of autosomal dominant spinocerebellar ataxia 12.

The intracellular domain of ErbB3 contains 6 recognition sites for the SH2 domain of the p85 subunit of PI3K. ErbB3 binding causes the allosteric activation of p110α, the lipid kinase subunit of PI3K, a function not found in either EGFR or ErbB2.

The human protein proteasome subunit alpha type-1 is also known as 20S proteasome subunit alpha-6 (based on systematic nomenclature). The protein is 30 kDa in size and composed of 263 amino acids. The calculated theoretical pI of this protein is 6.15.

This tiny but notable change is believed to be the reason the H subunit can bind faster, and the M subunit's catalytic activity isn't reduced when subjected to the same conditions as the H subunit, whereas the H subunit's activity is reduced fivefold.

Mediator of RNA polymerase II transcription subunit 4 also known as mediator complex subunit 4 (MED4), a component of Mediator or vitamin D3 receptor- interacting protein complex 36 kDa component (DRIP36) is a protein that in humans is encoded by the MED4 gene.

Prefoldin subunit 4 is a protein that in humans is encoded by the PFDN4 gene.

So far mutations in the delta subunit have not been associated with a specific disease.

CD49a is an integrin alpha subunit. It makes up half of the α1β1 integrin duplex.

GABRG3 is a subunit of the GABAA receptor for the neurotransmitter gamma-Aminobutyric acid (GABA).

Dynactin subunit 4 is a protein that in humans is encoded by the DCTN4 gene.

In 2009, a new nomenclature based on Eukaryotic Pol II subunit "Rpb" numbering was proposed.

FocA of E. coli is a symmetric pentamer, with each subunit consisting of six TMSs.

Two Sicilies coin The ' was a subunit of the Neapolitan, Sicilian, and Two Sicilies ducats.

Dynactin subunit 1 is a protein that in humans is encoded by the DCTN1 gene.

Coatomer subunit beta is a protein that in humans is encoded by the COPB1 gene.

Hemoglobin subunit delta is a protein that in humans is encoded by the HBD gene.

GFER has been shown to interact with COP9 constitutive photomorphogenic homolog subunit 5 and BNIPL.

Coatomer subunit alpha is a protein that in humans is encoded by the COPA gene.

Interleukin 12 receptor, beta 2 subunit has been shown to interact with Janus kinase 2.

Coatomer subunit epsilon is a protein that in humans is encoded by the COPE gene.

Methylosome subunit pICln is a protein that in humans is encoded by the CLNS1A gene.

Prefoldin subunit 6 is a protein that in humans is encoded by the PFDN6 gene.

Coatomer subunit beta' is a protein that in humans is encoded by the COPB2 gene.

Hemoglobin subunit epsilon is a protein that in humans is encoded by the HBE1 gene.

Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes ribosomal protein S4, a component of the 40S subunit. Ribosomal protein S4 is the only ribosomal protein known to be encoded by more than one gene, namely this gene, RPS4Y1 and the ribosomal protein S4, X-linked (RPS4X).

The Fo seems to have nine subunits (a, b, c, d, e, f, g, F6 and 8). This gene encodes the e subunit of the Fo complex. In yeast, the FO complex E subunit appears to play an important role in supporting F-ATPase dimerisation. This subunit is anchored to the inner mitochondrial membrane via its N-terminal region, which is involved in stabilising subunits G and K of the FO complex.

The ATP5MC2 gene is one of three human paralogs that encode membrane subunit c of the mitochondrial ATP synthase. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of two linked multi-subunit complexes: the soluble catalytic core, F1, and the membrane-spanning component, F0, comprising the proton channel.

NADH dehydrogenase [ubiquinone] iron-sulfur protein 7, mitochondrial, also knowns as NADH-ubiquinone oxidoreductase 20 kDa subunit, Complex I-20kD (CI-20kD), or PSST subunit is an enzyme that in humans is encoded by the NDUFS7 gene. The NDUFS7 protein is a subunit of NADH dehydrogenase (ubiquinone) also known as Complex I, which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

She also discovered a novel potassium channel beta subunit, cloned from human heart tissue. She found that this beta-subunit she discovered is generated from alternative splicing of a beta-subunit gene which gives rise to two other previously discovered beta- subunits. Her discovery of alternative splicing mechanisms suggests that potassium channel current diversity and heart tissue excitability diversity may be in part due to alternative splicing events. England completed her postdoctoral training in 1997.

XRCC4 protein is a tetramer that resembles the shape of a dumbbell containing two globular ends separated by a long, thin stalk. The tetramer is composed of two dimers, and each dimer is made up of two similar subunits. The first subunit (L) contains amino acid residues 1 – 203 and has a longer stalk than the second subunit (S) which contains residues 1 – 178. The globular N-terminal domains of each subunit are identical.

The ATP5MC3 gene is one of three human paralogs that encode membrane subunit c of the mitochondrial ATP synthase. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. ATP synthase is composed of two linked multi-subunit complexes: the soluble catalytic core, F1, and the membrane-spanning component, Fo, comprising the proton channel.

Therefore, PT subunit A will not be metabolized like most other proteins. PT is heat-stable and protease-resistant, but once the A and B are separated, these properties change. The B subunit will stay heat- stable at temperatures up to 60 °C, but it is susceptible to protein degradation. PT subunit A, on the other hand, is less susceptible to ubiquitin-dependent degradation, but is unstable at temperature of 37 °C.

Ribonuclease H2, subunit B is a protein that in humans is encoded by the RNASEH2B gene. RNase H2 is composed of a single catalytic subunit (A) and two non-catalytic subunits (B and C), and degrades the RNA of RNA:DNA hybrids. The non-catalytic B subunit of RNase H2 is thought to play a role in DNA replication. Mutations in this gene are a cause of Aicardi-Goutieres syndrome type 2 (AGS2).

Iron is stored as a hydrated ferric oxide mineral in its central cavity (about 80 Å diameter). The overall complex has cubic (432) symmetry. Each subunit includes a binuclear metalbinding site (the diiron site) linking together the four major helices of the subunit, which has been identified as the ferroxidase active site. Bfr from Pseudomonas aeruginosa (PaBfr), unlike other Bfrs, is found to contain two subunit types, which differ considerably in their amino acid sequences.

GoLoco motif is a protein structural motif. In heterotrimeric G-protein signalling, cell surface receptors (GPCRs) are coupled to membrane-associated heterotrimers comprising a GTP-hydrolyzing subunit G-alpha and a G-beta/G-gamma dimer. The inactive form contains the alpha subunit bound to GDP and complexes with the beta and gamma subunit. When the ligand is associated to the receptor, GDP is displaced from G-alpha and GTP is bound.

Exactly which RNAP they are most similar to is a topic of debate. Most other viruses that synthesize RNA use unrelated mechanics. Many viruses use a single-subunit DNA- dependent RNAP (ssRNAP) that is structurally and mechanistically related to the single-subunit RNAP of eukaryotic chloroplasts (RpoT) and mitochondria (POLRMT) and, more distantly, to DNA polymerases and reverse transcriptases. Perhaps the most widely studied such single-subunit RNAP is bacteriophage T7 RNA polymerase.

MT-CYB: mtDNA encoded cytochrome b; mutations associated with exercise intolerance CYC1:cytochrome c1 CYCS: cytochrome c UQCRFS1: Rieske iron sulfur protein UQCRB: Ubiquinone binding protein, mutation linked with mitochondrial complex III deficiency nuclear type 3 UQCRH: hinge protein UQCRC2: Core 2, mutations linked to mitochondrial complex III deficiency, nuclear type 5 UQCRC1: Core 1 UQCR: 6.4KD subunit UQCR10: 7.2KD subunit TTC19: Newly identified subunit, mutations linked to complex III deficiency nuclear type 2.

DNA-directed RNA polymerase II subunit RPB2 is an enzyme that in humans is encoded by the POLR2B gene. This gene encodes the second largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. This subunit, in combination with at least two other polymerase subunits, forms a structure within the polymerase that maintains contact in the active site of the enzyme between the DNA template and the newly synthesized RNA.

The gene PSMA2 encodes a member of the peptidase T1A family, that is a 20S core alpha subunit. Using FISH, the human gene HC3 (old nomenclature for PMSA2, 4.3kb with 3 exons) was mapped at chromosome band 6q27. The human protein proteasome subunit alpha type-2 is also known as 20S proteasome subunit alpha-2 (based on systematic nomenclature). The protein is 25.9 kDa in size and composed of 234 amino acids.

Threonine ammonia-lyase is a tetramer of identical subunits, and is arranged as a dimer of dimers. Each subunit has two domains: a domain containing the catalytic active site and a domain with allosteric regulatory sites. The two have been shown to be distinct regions, but the regulatory site of one subunit actually interacts with the catalytic site of another subunit. Both domains contain the repeating structural motif of beta sheets surrounded by alpha helices.

In mitochondria, the peripheral stalk is composed of one copy each of subunits OSCP (oligomycin sensitivity conferral protein), F6, b and d. There is no homologue of subunit F6 in bacterial or chloroplast F-ATPase, whose peripheral stalks are composed of one copy of the delta subunit (homologous to OSCP), and two copies of subunit b in bacteria, or one copy each of subunits b and b' in chloroplasts and photosynthetic bacteria.

Each subunit binds ions independently of the other, meaning conduction or exchange occur independently in each subunit. A cartoon representation of a CLC channel monomer. Two of these subunits come together to form the CLC channel. Each monomer has three binding sites for anions, Sext, Scen, and Sint. The two CBS domains bind adenosine nucleotides to alter channel function Each subunit consists of two related halves oriented in opposite directions, forming an ‘antiparallel’ structure.

In molecular biology, the NADH dehydrogenase (ubiquinone) 1 alpha subcomplex subunit 7 family of proteins (also known as NADH-ubiquinone oxidoreductase subunit B14.5a or Complex I-B14.5a) form a part of NADH dehydrogenase (complex I). In mammals, it is encoded by the NDUFA7 gene.

Cytochrome c oxidase subunit 5a is a protein that in humans is encoded by the COX5A gene. Cytochrome c oxidase 5A is a subunit of the cytochrome c oxidase complex, also known as Complex IV, the last enzyme in the mitochondrial electron transport chain.

Trifunctional enzyme subunit beta, mitochondrial (TP-beta) also known as 3-ketoacyl-CoA thiolase, acetyl-CoA acyltransferase, or beta-ketothiolase is an enzyme that in humans is encoded by the HADHB gene. HADHB is a subunit of the mitochondrial trifunctional protein and has thiolase activity.

Voltage-gated sodium channels normally consist of an alpha subunit that forms the ion conduction pore and one to two beta subunits that have several functions including modulation of channel gating. Expression of the alpha subunit alone is sufficient to produce a functional channel.

As with other nicotinic acetylcholine receptors, the α3β4 receptor is pentameric [(α3)m(β4)n where m + n = 5]. The exact subunit stoichiometry is not known and it is possible that more than one functional α3β4 receptor assembles in vivo with varying subunit stoichiometries.

Approximately 50% of patients with recessive infantile malignant osteopetrosis have mutations to the a3 subunit isoform of V-ATPase. In humans, 26 mutations have been identified in V-ATPase subunit isoform a3, found in osteoclasts, that result in the bone disease autosomal recessive osteopetrosis.

Guanine nucleotide-binding protein subunit alpha-11 is a protein that in humans is encoded by the GNA11 gene. Together with GNAQ (its paralogue), it functions as a Gq alpha subunit.139313 GUANINE NUCLEOTIDE-BINDING PROTEIN, ALPHA-11; GNA11 at OMIM. Retrieved January 1, 2015.

Interleukin 28 receptor, alpha subunit is a subunit for the interleukin-28 receptor. IL28RA is its human gene. The protein encoded by this gene belongs to the class II cytokine receptor family. This protein forms a receptor complex with interleukin 10 receptor, beta (IL10RB).

Histidine (His) residues are attached to the heme b3 in the small subunit. The hydrophilic region of the larger subunit has His and methionine (Met) ligands. Structure is similar to cytochrome oxidases. The active site is conserved between cNOR and qNOR, although differences (ie.

This is a heterodimer. Its α5 subunit is 36% identical to the GPIIb subunit. This complex is located mainly on endothelial cells but also on smooth muscle cells, macrophages and platelets. Its main function is in the adhesion of cells to the extracellular matrix components.

The fragment of 59 amino acids at peptide N-terminal is essential for proper protein folding and subsequent complex assembly. At the end-stage of complex assembly, the N-terminal fragment of beta5 subunit is cleaved, forming the mature beta5 subunit of 20S complex.

In prokaryotes and eukaryotes, it is an enzyme that consists of two polypeptide chains, a heavy and a light subunit, processed from a single chain precursor by an autocatalytic cleavage. The active site of GGT is known to be located in the light subunit.

Transducin is a 3-subunit guanine nucleotide-binding protein (G protein) which stimulates the coupling of rhodopsin and cGMP-phoshodiesterase during visual impulses. The transducin alpha subunits in rods and cones are encoded by separate genes. This gene encodes the alpha subunit in cones.

Small subunit 18S rDNA (SSU), nuclear ribosomal internal transcribed spacer (ITS) ITS1-5.8S-ITS2, and domains D2 and D2 of the large subunit 28S rDNA (LSU) were used to demarcate the fungal species M. granulomatis and differentiate it from closely related species, particularly M. viride.

Proposed biosynthesis of the activated aza-β-tyrosine subunit. The 2-aza-β-tyrosine subunit of kedarcidin chromophore is altogether unknown in any other natural product; this lack of precedence frustrates any attempt at a priori identification of the genes responsible for synthesizing this structure.

Integrator complex subunit 3 is a protein that in humans is encoded by the INTS3 gene.

Integrator complex subunit 9 is a protein that in Humans is encoded by the INTS9 gene.

BRISC complex subunit Abro1 is a protein that in humans is encoded by the FAM175B gene.

Integrator complex subunit 8 is a protein that in humans is encoded by the INTS8 gene.

Integrator complex subunit 7 is a protein that in humans is encoded by the INTS7 gene.

Carboxypeptidase N subunit 2 is an enzyme that in humans is encoded by the CPN2 gene.

Integrator complex subunit 11 is a protein that in humans is encoded by the CPSF3L gene.

CD49d is an integrin alpha subunit. It makes up half of the α4β1 lymphocyte homing receptor.

Acetylcholine receptor subunit delta is a protein that in humans is encoded by the CHRND gene.

WASH complex subunit 2C is a protein that in humans is encoded by the WASHC2C gene.

Coatomer subunit zeta-1 is a protein that in humans is encoded by the COPZ1 gene.

VPS37B, ESCRT-I subunit is a protein that in humans is encoded by the VPS37B gene.

Integrator complex subunit 1 is a protein that in humans is encoded by the INTS1 gene.

Hemoglobin subunit gamma-2 is a protein that in humans is encoded by the HBG2 gene.

Importin subunit alpha-1 is a protein that in humans is encoded by the KPNA1 gene.

Calpain-2 catalytic subunit is a protein that in humans is encoded by the CAPN2 gene.

Importin subunit beta-1 is a protein that in humans is encoded by the KPNB1 gene.

Laminin subunit alpha-5 is a protein that in humans is encoded by the LAMA5 gene.

Calpain-1 catalytic subunit is a protein that in humans is encoded by the CAPN1 gene.

Laminin subunit alpha-3 is a protein that in humans is encoded by the LAMA3 gene.

Proteasome inhibitor PI31 subunit is a protein that in humans is encoded by the PSMF1 gene.

Laminin subunit alpha-1 is a protein that in humans is encoded by the LAMA1 gene.

Laminin subunit alpha-4 is a protein that in humans is encoded by the LAMA4 gene.

Laminin subunit alpha-2 is a protein that in humans is encoded by the LAMA2 gene.

Laminin subunit beta-2 is a protein that in humans is encoded by the LAMB2 gene.

PGAM2 is one of two genes in humans encoding a PGAM subunit, the other being PGAM1.

This gene encodes the 25kD subunit of the protein complex, which is composed of four polypeptides.

FACT complex subunit SPT16 is a protein that in humans is encoded by the SUPT16H gene.

It also recruited the iron-sulphur PsaC subunit to further mitigate the risk of oxidative stress.

Integrator complex subunit 5 is a protein that in humans is encoded by the INTS5 gene.

Protein farnesyltransferase subunit beta is an enzyme that in humans is encoded by the FNTB gene.

Hemoglobin subunit gamma-1 is a protein that in humans is encoded by the HBG1 gene.

Coatomer subunit gamma-2 is a protein that in humans is encoded by the COPG2 gene.

Diazaborine B is a chemical compound that inhibits maturation of rRNAs for the large ribosomal subunit.

SRP receptor alpha subunit is a protein that in humans is encoded by the SRPRA gene.

Mediator complex subunit 13 is a protein that in humans is encoded by the MED13 gene.

The γ subunit is the site of the enzyme's catalytic activity while the other three subunits serve regulatory functions. When unmodified, the α and β subunits inhibit the enzyme's catalysis, but phosphorylation of both these subunits by protein kinase A (PKA, or cAMP-dependent protein kinase) reduces their respective inhibitory activities. The δ subunit is the ubiquitous eukaryotic protein calmodulin which itself has 4 calcium ion binding sites. When cytosolic Ca2+ levels rise-to as low as 10−7 M—the δ subunit undergoes a large conformational change that activates the kinase's activity by binding to a complementary hydrophobic patch on the catalytic γ subunit.

For example, Escherichia coli HycI is involved in processing of pre-HycE (the large subunit of hydrogenase 3),; HybD is involved in processing of pre-HybC (the large subunit of hydrogenase 2); and HyaD is assumed to be involved in processing of the large subunit of hydrogenase 1. The cleavage site is after a His or an Arg, liberating a short peptide. This cleavage occurs only in the presence of nickel, and the endopeptidase probably uses the metal in the large subunit of [NiFe]-hydrogenases as a recognition motif. There is no direct evidence for the active site or substrate-binding site, but there are predictions based on an available structure.

Choriogonadotropin subunit beta variant 1 is a protein that in humans is encoded by the CGB1 gene. The beta subunit of chorionic gonadotropin (CGB) is encoded by six highly homologous and structurally similar genes that are arranged in tandem and inverted pairs on chromosome 19q13.3, and contiguous with the luteinizing hormone beta (LHB) subunit gene. The CGB genes are primarily distinguished by differences in the 5' untranslated region. This gene was originally thought to be one of the two pseudogenes (CGB1 and CGB2) of CGB subunit, however, detection of CGB1 and CGB2 transcripts in vivo, and their presence on the polysomes, suggested that these transcripts are translated.

Choriogonadotropin subunit beta variant 2 is a protein that in humans is encoded by the CGB2 gene. The beta subunit of chorionic gonadotropin (CGB) is encoded by six highly homologous and structurally similar genes that are arranged in tandem and inverted pairs on chromosome 19q13.3, and contiguous with the luteinizing hormone beta (LHB) subunit gene. The CGB genes are primarily distinguished by differences in the 5' untranscribed region. This gene was originally thought to be one of the two pseudogenes (CGB1 and CGB2) of CGB subunit, however, detection of CGB1 and CGB2 transcripts in vivo, and their presence on the polysomes, suggested that these transcripts are translated.

This subunit is a key component of the proton channel, and may play a direct role in the translocation of protons across the membrane. Catalysis in the F1 complex depends upon the rotation of the central stalk and Fo c-ring, which in turn is driven by the flux of protons through the membrane via the interface between the F0 c-ring and subunit A. The peripheral stalk links subunit A to the external surface of the F1 domain, and is thought to act as a stator to counter the tendency of subunit A and the F1alpha3 beta3 catalytic portion to rotate with the central rotary element.

In enzymology, a trimethylamine-N-oxide reductase (cytochrome c) () is an enzyme that catalyzes the chemical reaction :trimethylamine + 2 (ferricytochrome c)-subunit + H2O \rightleftharpoons trimethylamine N-oxide + 2 (ferrocytochrome c)-subunit + 2 H+ The 3 substrates of this enzyme are trimethylamine, (ferricytochrome c)-subunit, and H2O, whereas its 3 products are trimethylamine N-oxide, (ferrocytochrome c)-subunit, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on other nitrogenous compounds as donors with a cytochrome as acceptor. The systematic name of this enzyme class is trimethylamine:cytochrome c oxidoreductase. Other names in common use include TMAO reductase, and TOR. This enzyme participates in two-component system - general.

ATPase, subunit C of Fo/Vo complex is the main transmembrane subunit of V-type, A-type and F-type ATP synthases. Subunit C (also called subunit 9, or proteolipid in F-ATPases, or the 16 kDa proteolipid in V-ATPases) was found in the Fo or Vo complex of F- and V-ATPases, respectively. The subunits form an oligomeric c ring that make up the Fo/Vo/Ao rotor, where the actual number of subunits vary greatly among specific enzymes. ATPases (or ATP synthases) are membrane-bound enzyme complexes/ion transporters that combine ATP synthesis and/or hydrolysis with the transport of protons across a membrane.

In prokaryotes, subunits I and III can be fused and a fourth subunit is sometimes found, whereas in eukaryotes there are a variable number of additional small subunits. As the bacterial respiratory systems are branched, they have a number of distinct terminal oxidases, rather than the single cytochrome c oxidase present in the eukaryotic mitochondrial systems. Although the cytochrome o oxidases do not catalyze the cytochrome c but the quinol (ubiquinol) oxidation they belong to the same haem-copper oxidase superfamily as cytochrome c oxidases. Members of this family share sequence similarities in all three core subunits: subunit I is the most conserved subunit, whereas subunit II is the least conserved.

Cytochrome c oxidase subunit VIa polypeptide 2 is a protein that in humans is encoded by the COX6A2 gene. Cytochrome c oxidase 6A2 is a subunit of the cytochrome c oxidase complex, also known as Complex IV, the last enzyme in the mitochondrial electron transport chain.

Cytochrome c oxidase subunit VIb polypeptide 2 is a protein that in humans is encoded by the COX6B2 gene. Cytochrome c oxidase 6B2 is a subunit of the cytochrome c oxidase complex, also known as Complex IV, the last enzyme in the mitochondrial electron transport chain.

In addition, RIOK1 has also a potential role with the metabolism of the 40S ribosomal subunit, precisely, we know it's involved in the maturation of the 40S ribosomal subunit and needed for the recycling of PNO1 and NOB1, which are both RNA- binding proteins from 40S precursors.

Guanine nucleotide-binding protein G(q) subunit alpha is a protein that in humans is encoded by the GNAQ gene. Together with GNA11 (its paralogue), it functions as a Gq alpha subunit.139313 GUANINE NUCLEOTIDE-BINDING PROTEIN, ALPHA-11; GNA11 at OMIM. Retrieved January 1, 2015.

PI-3K is one of the important components in the regulation of the insulin signaling pathway. It maintains the insulin sensitivity in the liver. PI-3K is composed of a regulatory subunit (P85) and a catalytic subunit (P110). P85 regulates the activation of PI-3K enzyme.

This subunit, like most other dynactin subunits, exists only as a part of the dynactin complex. It is primarily an alpha-helical protein with very little coiled coil, and binds directly to the largest subunit (p150) of dynactin. Alternative splicing of this gene generates 2 transcript variants.

Guanine nucleotide-binding protein G(t) subunit alpha-3, also known as gustducin alpha-3 chain, is a protein that in humans is encoded by the GNAT3 gene. Gustducin alpha-3 chain is a subunit of the heterotrimeric protein gustducin that is responsible for basic taste.

The V1 domain consists of three A, three B, and two G subunits, as well as a C, D, E, F, and H subunit. The V1 domain contains the ATP catalytic site. This gene encodes alternate transcriptional splice variants, encoding different V1 domain C subunit isoforms.

Large subunit ribosomal ribonucleic acid (LSU rRNA) is the largest of the two major RNA components of the ribosome. Associated with a number of ribosomal proteins, the LSU rRNA forms the large subunit of the ribosome. The LSU rRNA acts as a ribozyme, catalyzing peptide bond formation.

Modulation of the α1 subunit is associated with sedation, motor impairment, respiratory depression, amnesia, ataxia, and reinforcing behavior (drug-seeking behavior). Modulation of the α2 subunit is associated with anxiolytic activity and disinhibition. For this reason, certain benzodiazepines may be better suited to treat insomnia than others.

One α and one β subunit associate non-covalently to form 24 unique integrins found in mammals. While some β integrin subunits partner with multiple α subunits, β6 associates exclusively with the αv subunit. Thus, the function of ITGB6 is entirely associated with the integrin αvβ6.

This gene encodes an integral subunit of TFIID associated with all transcriptionally competent forms of that complex. This subunit interacts strongly with two TFIID subunits that show similarity to histones H3 and H4, and it may participate in forming a nucleosome-like core in the TFIID complex.

Meprin A subunit alpha also known as endopeptidase-2 or PABA peptide hydrolase is the alpha subunit of the meprin A enzyme that in humans is encoded by the MEP1A gene. The MEP1A locus is on chromosome 6p in humans and on chromosome 17 in mice.

Molecular analyses based on either a single locus (small subunit rRNA) or several loci (SSU rDNA, large subunit rRNA, ITS1-5.8S-ITS2 region, alpha-tubulin and COI) showed that Condylostoma is phylogenetically related to the genera Condylostentor and Chattonidium, and with Condylostomides possibly being their sister-group.

The active, assembled toxin is a tripartite structure with three distinct subunits- CdtA, CdtB, and CdtC. In terms of function, it is an AB toxin. In this context, the CdtB subunit is actually the catalytically active "A" subunit, and the CdtA and CdtC together form the binding "B" subunit, which helps the toxin bind and enter target cells. Some literature refers to the toxin structure as AB2 to reflect the presence of both CdtA and CdtC.

The proton pump, H+/K+ ATPase is a α,β-heterodimeric enzyme. The catalytic α subunit has ten transmembrane segments with a cluster of intramembranal carboxylic amino acids located in the middle of the transmembrane segments TM4, TM5, TM6 and TM8. The β subunit has one transmembrane segment with N terminus in cytoplasmic region. The extracellular domain of the β subunit contains six or seven N-linked glycosylation sites which is important for the enzyme assembly, maturation and sorting.

Voltage-dependent calcium channel gamma-1 subunit is a protein that in humans is encoded by the CACNG1 gene. L-type calcium channels are composed of five subunits. The protein encoded by this gene represents one of these subunits, gamma, and is one of several gamma subunit proteins. This particular gamma subunit is part of skeletal muscle 1,4-dihydropyridine-sensitive calcium channels and is an integral membrane protein that plays a role in excitation- contraction coupling.

Telithromycin prevents bacteria from growing, by interfering with their protein synthesis. Telithromycin binds to the subunit 50S of the bacterial ribosome, and blocks the progression of the growing polypeptide chain. Telithromycin has over 10 times higher affinity to the subunit 50S than erythromycin. In addition, telithromycin strongly bind simultaneously to two domains of 23S RNA of the 50 S ribosomal subunit, where older macrolides bind strongly only to one domain and weakly to the second domain.

Eukaryotic RNA-polymerase II of Saccharomyces cerevisiae, with the RPB1 subunit coloured in red. Other subunits: RPB3 – orange , RPB11 – yellow , RPB2 – wheat, RPB6 – pink; the remaining seven subunits are in grey colour. The RNA polymerase II subunit RPB1 is the largest subunit of the RNA polymerase II. In Saccharomyces cerevisiae, it is encoded by the RPO21 gene. PCR amplification success of RPB1 is very taxon-dependent, ranging from 70-80% in Ascomycota to 14% in early diverging fungal lineages.

Therefore, this inhibition of an ion current usually produced by NMDAR activation leads to decreased LTP in hippocampal areas. Alcohol negatively affects LTP to a greater degree in immature versus mature animals. In adolescents, alcohol decreases the expression of both the NMDAR NR2A subunit in the hippocampus and the NR1 subunit in the prefrontal cortex. Studies have also found that a decrease in phosphorylation of 2B subunit in the prefrontal cortex, the hippocampus, the nucleus accumbens, and the striatum.

CDK5 regulatory subunit-associated protein 1 is a protein that in humans is encoded by the CDK5RAP1 gene. Neuronal CDC2-like kinase, which is involved in the regulation of neuronal differentiation, is composed of a catalytic subunit, CDK5, and an activating subunit, p25NCK5A. The protein encoded by this gene binds to p25NCK5A and therefore may be involved in neuronal differentiation. Multiple transcript variants exist for this gene, but the full-length natures of only two have been determined.

Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with 24 transmembrane domains and one or more regulatory beta subunits. They are responsible for the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family, and is found in a cluster of five alpha subunit genes on chromosome 2. Multiple transcript variants encoding different isoforms have been found for this gene.

Inhibins are heterodimeric glycoproteins composed of an α subunit (INHA) and one of two homologous, but distinct, β subunits (βA or βB, this protein). mRNA for the two subunits has been demonstrated in the testes of adult rats. Inhibin can bind specifically to testicular interstitial cells throughout development and may be an important regulator of Leydig cell testosterone production or interstitial cell function. The inhibin beta B subunit joins the α subunit to form a pituitary FSH secretion inhibitor.

The R-type calcium channel is a type of voltage-dependent calcium channel. Like the others of this class, the α1 subunit forms the pore through which calcium enters the cell and determines most of the channel's properties. This α1 subunit is also known as the calcium channel, voltage-dependent, R type, alpha 1E subunit (CACNA1E) or Cav2.3 which in humans is encoded by the CACNA1E gene. They are strongly expressed in cortex, hippocampus, striatum, amygdala and interpeduncular nucleus.

The α2 region is in the extracellular space while the δ region is in the cell membrane and have been seen to be anchored with a glycosylphosphatidylinositol (GPI) anchor. The γ subunit has eight isoforms (γ1-γ8) and is connected to the α1 subunit and has only been found in muscle cells in the CaV1.1 and CaV1.2 channels. Not much is known about the γ subunit, but it has been linked to interactions in hydrophobic forces.

There is only one recognition site on the catalytic subunit, making the association of a regulatory subunit mutually exclusive (Egloff et al., 1997). The catalytic subunit of ceramide- activated PP1 is a single-domain protein consisting of a central β-sandwich, of two mixed β-sheets, with seven α-helices surrounding the sandwich on one side and a sub-domain consisting of three α-helices and a β-sheet on the opposite side (Egloff et al., 1997).

DNA-directed RNA polymerase II subunit RPB4 is an enzyme that in humans is encoded by the POLR2D gene. This gene encodes the fourth-largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. In yeast, this polymerase subunit is associated with the polymerase under suboptimal growth conditions and may have a stress protective role. A sequence for a ribosomal pseudogene is contained within the 3' untranslated region of the transcript from this gene.

The AB5 toxins are six-component protein complexes secreted by certain pathogenic bacteria known to cause human diseases such as cholera, dysentery, and hemolytic–uremic syndrome. One component is known as the A subunit, and the remaining five components are B subunits. All of these toxins share a similar structure and mechanism for entering targeted host cells. The B subunit is responsible for binding to receptors to open up a pathway for the A subunit to enter the cell.

DNA-directed RNA polymerases I, II, and III subunit RPABC2 is a protein that in humans is encoded by the POLR2F gene. This gene encodes the sixth largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes, that is also shared by the other two DNA-directed RNA polymerases. In yeast, this polymerase subunit, in combination with at least two other subunits, forms a structure that stabilizes the transcribing polymerase on the DNA template.

Eukaryotic translation initiation factor 2 (eIF2) functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA and binding to a 40S ribosomal subunit. eIF2 is composed of three subunits, alpha (α), beta (β, this article), and gamma (γ), with the protein encoded by this gene representing the beta subunit. The beta subunit catalyzes the exchange of GDP for GTP, which recycles the eIF2 complex for another round of initiation.

Neuronal acetylcholine receptor subunit alpha-1, also known as nAChRα1, is a protein that in humans is encoded by the CHRNA1 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR). The muscle acetylcholine receptor consists of 5 subunits of 4 different types: 2 alpha isoforms and 1 each of beta, gamma, and delta subunits.2 This gene encodes an alpha subunit that plays a role in acetylcholine binding/channel gating.

This gene encodes the F6 subunit of the FO complex, required for F1 and FO interactions. Alternatively spliced transcript variants encoding different isoforms have been identified for this gene. The F6 subunit is part of the peripheral stalk that links the F1 and FO complexes together, and which acts as a stator to prevent certain subunits from rotating with the central rotary element. The peripheral stalk differs in subunit composition between mitochondrial, chloroplast and bacterial F-ATPases.

STAGA complex 65 subunit gamma is a protein that in humans is encoded by the SUPT7L gene.

Interleukin 27 receptor, alpha is a subunit of the interleukin-27 receptor. IL27RA is its human gene.

Mediator complex subunit 9 (Med9) is a protein that in humans is encoded by the MED9 gene.

Mediator complex subunit 10 (Med10) is a protein that in humans is encoded by the MED10 gene.

Mediator complex subunit 11 (Med11) is a protein that in humans is encoded by the MED11 gene.

Mediator complex subunit 18 (Med18) is a protein that in humans is encoded by the MED18 gene.

Mediator complex subunit 19 (Med19) is a protein that in humans is encoded by the MED19 gene.

Ribonuclease P protein subunit p29 is an enzyme that in humans is encoded by the POP4 gene.

DNA polymerase epsilon subunit 2 is an enzyme that in humans is encoded by the POLE2 gene.

Anaphase-promoting complex subunit 11 is an enzyme that in humans is encoded by the ANAPC11 gene.

Splicing factor 3B subunit 5 is a protein that in humans is encoded by the SF3B5 gene.

Sodium channel subunit beta-2 is a protein that in humans is encoded by the SCN2B gene.

BRCA1-A complex subunit RAP80 is a protein that in humans is encoded by the UIMC1 gene.

Histone deacetylase complex subunit SAP130 is an enzyme that in humans is encoded by the SAP130 gene.

This gene encodes the p80 subunit. This protein is a member of the AAA family of ATPases.

Histone deacetylase complex subunit SAP18 is an enzyme that in humans is encoded by the SAP18 gene.

BRCA1-A complex subunit BRE is a protein that in humans is encoded by the BRE gene.

COP9 signalosome complex subunit 7b is a protein that in humans is encoded by the COPS7B gene.

COP9 signalosome complex subunit 7a is a protein that in humans is encoded by the COPS7A gene.

26S proteasome complex subunit DSS1 is a protein that in humans is encoded by the SHFM1 gene.

KIF3B has been shown to interact with the SMC3 subunit of the cohesin complex and with RAB4A.

Ribonuclease P protein subunit p30 is an enzyme that in humans is encoded by the RPP30 gene.

Ribonuclease P protein subunit p38 is an enzyme that in humans is encoded by the RPP38 gene.

Ribonuclease P protein subunit p14 is an enzyme that in humans is encoded by the RPP14 gene.

Anaphase-promoting complex subunit 10 is an enzyme that in humans is encoded by the ANAPC10 gene.

Large subunit GTPase 1 homolog is an enzyme that in humans is encoded by the LSG1 gene.

BRCA1-A complex subunit MERIT40 is a protein that in humans is encoded by the BABAM1 gene.

Glycine receptor subunit alpha-2 is a protein that in humans is encoded by the GLRA2 gene.

Heteromeric Kv2.1/Kv9.3 channels form with fixed stoichiometry consisting of three Kv2.1 subunits and one Kv9.3 subunit.

Mitochondrial import receptor subunit TOM40B is a protein that in humans is encoded by the TOMM40L gene.

Origin recognition complex subunit 1 is a protein that in humans is encoded by the ORC1 gene.

TRNA splicing endonuclease subunit 54 is a protein that in humans is encoded by the TSEN54 gene.

The synthase has a 40-aa insert in the gamma-subunit to inhibit wasteful activity when dark.

Mediator complex subunit 20 (Med20) is a protein that in humans is encoded by the MED20 gene.

These disulfide bonds in HEF2 allows the subunit to perform large conformational changes that catalyze membrane fusion.

Casein kinase II subunit alpha' is an enzyme that in humans is encoded by the CSNK2A2 gene.

AP-2 complex subunit mu is a protein that in humans is encoded by the AP2M1 gene.

COP9 signalosome complex subunit 6 is a protein that in humans is encoded by the COPS6 gene.

Proteasome activator complex subunit 1 is a protein that in humans is encoded by the PSME1 gene.

Glutamate—cysteine ligase catalytic subunit is an enzyme that in humans is encoded by the GCLC gene.

Proteasome activator complex subunit 3 is a protein that in humans is encoded by the PSME3 gene.

Replication factor C subunit 1 is a protein that in humans is encoded by the RFC1 gene.

Proteasome activator complex subunit 2 is a protein that in humans is encoded by the PSME2 gene.

Replication factor C subunit 2 is a protein that in humans is encoded by the RFC2 gene.

SWI/SNF complex subunit SMARCC2 is a protein that in humans is encoded by the SMARCC2 gene.

Replication factor C subunit 4 is a protein that in humans is encoded by the RFC4 gene.

Replication factor C subunit 3 is a protein that in humans is encoded by the RFC3 gene.

Replication factor C subunit 5 is a protein that in humans is encoded by the RFC5 gene.

Splicing factor 3B subunit 1 is a protein that in humans is encoded by the SF3B1 gene.

Splicing factor 3A subunit 2 is a protein that in humans is encoded by the SF3A2 gene.

Splicing factor 3B subunit 2 is a protein that in humans is encoded by the SF3B2 gene.

Glutamate [NMDA] receptor subunit 3A is a protein that in humans is encoded by the GRIN3A gene.

SWI/SNF complex subunit SMARCC1 is a protein that in humans is encoded by the SMARCC1 gene.

AP-2 complex subunit beta is a protein that in humans is encoded by the AP2B1 gene.

Proteasome activator complex subunit 4 is a protein that in humans is encoded by the PSME4 gene.

Pyruvate dehydrogenase phosphatase regulatory subunit is a protein that in humans is encoded by the PDPR gene.

Ribonuclease P protein subunit p40 is an enzyme that in humans is encoded by the RPP40 gene.

Ribonuclease P protein subunit p20 is an enzyme that in humans is encoded by the POP7 gene.

SUMO-activating enzyme subunit 1 is a protein that in humans is encoded by the SAE1 gene.

Splicing factor 3B subunit 4 is a protein that in humans is encoded by the SF3B4 gene.

Glutamate [NMDA] receptor subunit 3B is a protein that in humans is encoded by the GRIN3B gene.

RISC-loading complex subunit TARBP2 is a protein that in humans is encoded by the TARBP2 gene.

Glycine receptor subunit alpha-1 is a protein that in humans is encoded by the GLRA1 gene.

Catsper channel auxiliary subunit epsilon is a protein that in humans is encoded by the CATSPERE gene.

Inhibin, activin, and sex hormones do not affect genetic activity for the beta subunit production of LH.

Integrin subunit beta like 1 is a protein that in humans is encoded by the ITGBL1 gene.

CCR4-NOT transcription complex subunit 6 is a protein that in humans is encoded by the CNOT6 gene. The protein encoded by this gene is a subunit of the CCR4-Not transcriptional regulation and deadenylase complex. The encoded protein has a 3'-5' exonuclease activity and prefers polyadenylated substates.

Between attacks they have nystagmus and dysarthria. These patients are responsive to acetazolamide. Both juvenile myoclonic epilepsy and EA5 are a result of mutations in CACNB4, a gene that encodes the calcium channel β4 subunit. This subunit coassembles with α-subunits and produces channels that slowly inactivate after opening.

The Fo seems to have nine subunits (a, b, c, d, e, f, g, F6 and 8). This gene encodes the g subunit of the F0 complex. The function of subunit G is currently unknown. There is no counterpart in chloroplast or bacterial F-ATPases identified so far.

The factor consists of an alpha, beta, and gamma subunit. The eIF2 gamma subunit is characterized by a GTP-binding domain and beta-barrel folds. It binds to the tRNA through GTP. Once the initiation factor helps the tRNA bind, the GTP hydrolyzes and is released the eIF2.

AP2 adaptor complex associates with the plasma membrane and is responsible for endocytosis. AP3 is responsible for protein trafficking to lysosomes and other related organelles. AP4 is less well characterised. AP complexes are heterotetramers composed of two large subunits (adaptins), a medium subunit (mu) and a small subunit (sigma).

INTS1 is a subunit of the Integrator complex, which associates with the C-terminal domain of RNA polymerase II large subunit (POLR2A; MIM 180660) and mediates 3-prime end processing of small nuclear RNAs U1 (RNU1; MIM 180680) and U2 (RNU2; MIM 180690) (Baillat et al., 2005 [PubMed 16239144]).

This subunit tends to associate with alpha 6 subunit and is likely to play a pivotal role in the biology of invasive carcinoma. Mutations in this gene are associated with epidermolysis bullosa with pyloric atresia. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene.

26S proteasome non-ATPase regulatory subunit 4, also as known as 26S Proteasome Regulatory Subunit Rpn10 (systematic nomenclature), is an enzyme that in humans is encoded by the PSMD4 gene. This protein is one of the 19 essential subunits that contributes to the complete assembly of 19S proteasome complex.

26S proteasome non-ATPase regulatory subunit 1, also as known as 26S Proteasome Regulatory Subunit Rpn2 (systematic nomenclature), is a protein that in humans is encoded by the PSMD1 gene. This protein is one of the 19 essential subunits that contributes to the complete assembly of 19S proteasome complex.

In molecular biology, the CD20-like family of proteins includes the CD20 protein and the beta subunit of the high affinity receptor for IgE Fc, MS4A2. MS4A2 has a tetrameric structure consisting of a single IgE-binding alpha subunit, a single beta subunit, and two disulfide-linked gamma subunits. It has four putative transmembrane segments and a probable topology where both amino- and carboxy termini protrude into the cytoplasm. This family also includes LR8 like proteins from humans (TMEM176B), mice and rats.

Phosphatidylinositol-4,5-bisphosphate 3-kinase (also called phosphatidylinositol 3-kinase (PI3K)) is composed of an 85 kDa regulatory subunit and a 110 kDa catalytic subunit. The protein encoded by this gene represents the catalytic subunit, which uses ATP to phosphorylate phosphatidylinositols (PtdIns), PtdIns4P and PtdIns(4,5)P2. The involvement of p110α in human cancer has been hypothesized since 1995. Support for this hypothesis came from genetic and functional studies, including the discovery of common activating PIK3CA missense mutations in common human tumors.

Specifically, the δ-subunit is usually expressed in GABAA receptors associated with extrasynaptic activity. The most common GABAA receptors have the gamma subunit, which allows the receptor to bind benzodiazepines. For this reason, receptors containing δ-subunits are sometimes referred to as “benzodiazepine insensitive” GABAA receptors. The δ-subunit containing receptors are also known to be involved in the ventral tegmental area (VTA) pathway in the brain's hippocampus, which means that they may have implications in learning, memory, and reward.

This gene encodes platelet-activating factor acetylhydrolase isoform 2, a single-subunit intracellular enzyme that catalyzes the removal of the acetyl group at the SN-2 position of platelet- activating factor (identified as 1-O-alkyl-2-acetyl-sn- glyceryl-3-phosphorylcholine). However, this lipase exhibits a broader substrate specificity than simply platelet activating factor. Two other isoforms of intracellular platelet-activating factor acetylhydrolase exist, and both are multi-subunit enzymes. Additionally, there is a single-subunit serum isoform of this enzyme.

The primary structures of all four ENaC subunits show strong similarity. Thus, these four proteins represent a family of proteins that share a common ancestor. In global alignment (meaning alignments of sequences along their entire length and not just a partial segment), the human δ subunit shares 34% identity with the α subunit and 23% identity with the β and γ subunits. All four ENaC subunit sequences have two hydrophobic stretches that form two transmembrane segments named as TM1 and TM2.

The sm-M20 is suggested to play a regulatory role in muscle contraction by binding to MBS. MBS is also encoded by another gene, myosin light chain phosphatase target subunit 1. sm-M20 shows higher binding affinity to this gene product than to myosin light chain phosphatase target subunit 2-MBS even though the two MBS proteins are highly similar. Although both MBSs increase the activity of MLCP, myosin light chain phosphatase target subunit 1-MBS is a more efficient activator.

Subunit C consists of hydrophobic membrane-spanning, primarily helical segments and is the site of quinol oxidization. In some fumarate reductase structures, one or more heme groups are additionally bound to the C subunit and participate in the electron transfer. The D subunit contains hydrophobic alpha helices that span the membrane, but does not participate in the catalytic action of the enzyme. It may be required to anchor the catalytic components of the fumarate reductase complex to the cytoplasmic membrane.

Protein geranylgeranyltransferase type I (GGTase-I) transfers a geranylgeranyl group to the cysteine residue of candidate proteins containing a C-terminal CAAX motif in which 'A' is an aliphatic amino acid and 'X' is leucine (summarized by Zhang et al., 1994 [PubMed 8106351]). The enzyme is composed of a 48-kD alpha subunit (FNTA; MIM 134635) and a 43-kD beta subunit, encoded by the PGGT1B gene. The FNTA gene encodes the alpha subunit for both GGTase-I and the related enzyme farnesyltransferase.

This structural change causes an increased affinity for the regulatory protein called transducin (a type of G protein). Upon binding to rhodopsin, the alpha subunit of the G protein replaces a molecule of GDP with a molecule of GTP and becomes activated. This replacement causes the alpha subunit of the G protein to dissociate from the beta and gamma subunits of the G protein. As a result, the alpha subunit is now free to bind to the cGMP phosphodiesterase (an effector protein).

The NMDA receptor is made up of three subunits: NR1, a variable NR2 subunit, and a variable NR3 subunit. Two NR2 subunits in particular have been the subject of intense study: NR2A and NR2B. The NR2B subunit not only is more sensitive to glutamate and takes longer to desensitize, but also allows more calcium entrance into the cell when it opens. A low NR2A/NR2B ratio is generally correlated with a decreased threshold of activation caused by rearing animals in light-deprived environments.

Recently an alternative proteasome was identified in human cells that lack the α3 core subunit. These proteasomes (known as the α4-α4 proteasomes) instead form 20S core particles containing an additional α4 subunit in place of the missing α3 subunit. These alternative 'α4-α4' proteasomes have been known previously to exist in yeast. Although the precise function of these proteasome isoforms is still largely unknown, cells expressing these proteasomes show enhanced resistance to toxicity induced by metallic ions such as cadmium.

In structural biology, a protomer is the structural unit of an oligomeric protein. It is the smallest unit composed of at least two different protein chains that form a larger hetero-oligomer by association of two or more copies of this unit. The term was introduced by Chetverin to make nomenclature in the Na/K-ATPase enzyme unambiguous. This enzyme is composed of two subunits, a large catalytic subunit, alpha and a smaller glycoprotein subunit, beta (plus a proteolipid, called γ-subunit).

The first hydrogenase is a regulatory hydrogenase (RH) that signals to the cell hydrogen is present. The RH is a protein containing large and small [Ni-Fe] hydrogenase subunits attached to a histidine protein kinase subunit. The hydrogen gas is oxidized at the [Ni-Fe] center in the large subunit and in turn reduces the [Fe-S] clusters in the small subunit. It is unknown whether the electrons are transferred from the [Fe-S] clusters to the protein kinase domain.

This gene encodes a subunit of the elongation factor-1 complex, which is responsible for the enzymatic delivery of aminoacyl tRNAs to the ribosome. This subunit functions as guanine nucleotide exchange factor. It is reported that this subunit interacts with HIV-1 Tat, and thus it represses the translation of host-cell, but not HIV-1, mRNAs. Several alternatively spliced transcript variants have been found for this gene, however, the full length nature of only two variants has been determined.

The primary structures of all four ENaC subunits show strong similarity. Thus, these four proteins represent a family of proteins that share a common ancestor. In global alignment (meaning alignments of sequences along their entire length and not just a partial segment), the human β subunit shares 34% identity with the γ subunit and 26 and 23% identity with the α and δ subunits. All four ENaC subunit sequences have two hydrophobic stretches that form two transmembrane segments named as TM1 and TM2.

This gene belongs to the splicing factor SR family of genes. U2 auxiliary factor, comprising a large and a small subunit, is a non-snRNP protein required for the binding of U2 snRNP to the pre-mRNA branch site. This gene encodes the small subunit which plays a critical role in both constitutive and enhancer-dependent RNA splicing by directly mediating interactions between the large subunit and proteins bound to the enhancers. Alternatively spliced transcript variants encoding different isoforms have been identified.

The primary structures of all four ENaC subunits show strong similarity. Thus, these four proteins represent a family of proteins that share a common ancestor. In global alignment (meaning alignments of sequences along their entire length and not just a partial segment), the human α subunit shares 34% identity with the δ subunit and 26-27% identity with the β and γ subunits. All four ENaC subunit sequences have two hydrophobic stretches that form two transmembrane segments named as TM1 and TM2.

The primary structures of all four ENaC subunits show strong similarity. Thus, these four proteins represent a family of proteins that share a common ancestor. In global alignment (meaning alignments of sequences along their entire length and not just a partial segment), the human γ subunit shares 34% identity with the β subunit and 27 and 23% identity with the α and δ subunits. All four ENaC subunit sequences have two hydrophobic stretches that form two transmembrane segments named as TM1 and TM2.

EIF6 exists both in nucleolus and cytoplasm. In the eukaryotic nucleolus, a 90S pre-ribosomal complex separate to a 60S pre-ribosomal complex and a 40S pre- ribosomal complex, which are involved in synthesis of mature ribosome. EIF6 is indispensable in 60S subunit biogenesis and deletion of EIF6 has lethal effect. The partial deletion of eIF6 results in decreasing of free 60S ribosomal subunit, which means it knocks the 40S/60S subunit ratio off balance, and limiting the speed of protein synthesis.

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta isoform is an enzyme that in humans is encoded by the PIK3CB gene. Phosphoinositide 3-kinases (PI3Ks) phosphorylate the 3-prime OH position of the inositol ring of inositol lipids. They have been implicated as participants in signaling pathways regulating cell growth by virtue of their activation in response to various mitogenic stimuli. PI3Ks are composed of a 110-kD catalytic subunit, such as PIK3CB, and an 85-kD adaptor subunit (Hu et al.

The elongation of primed DNA templates by DNA polymerase delta and DNA polymerase epsilon requires the accessory proteins proliferating cell nuclear antigen (PCNA) and replication factor C (RFC). RFC, also named activator 1, is a protein complex consisting of five distinct subunits of 140, 40, 38, 37, and 36 kDa. This gene encodes the 38 kDa subunit. This subunit is essential for the interaction between the 140 kDa subunit and the core complex that consists of the 36, 37, and 40 kDa subunits.

The flexible loop (Phe92–Ser108), pyrophosphate binding loop (Asp171–Gly174), and flag region (Val30–Ile44 from an adjacent subunit) comprise the ATP binding site, located at the interface between two domains of one subunit. The flexible loop is so named because of its large variability in conformation. The ribose 5-phosphate binding site consists of residues Asp220–Thr228, located in the C-terminal domain of one subunit. The allosteric site, which binds ADP, consists of amino acid residues from three subunits.

NADH dehydrogenase [ubiquinone] iron-sulfur protein 8, mitochondrial also known as NADH-ubiquinone oxidoreductase 23 kDa subunit, Complex I-23kD (CI-23kD), or TYKY subunit is an enzyme that in humans is encoded by the NDUFS8 gene. The NDUFS8 protein is a subunit of NADH dehydrogenase (ubiquinone) also known as Complex I, which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain. Mutations in this gene have been associated with Leigh syndrome.

The two ends of an actin filament differ in their dynamics of subunit addition and removal. They are thus referred to as the plus end (with faster dynamics, also called barbed end) and the minus end (with slower dynamics, also called pointed end). This difference results from the fact that subunit addition at the minus end requires a conformational change of the subunits. Note that each subunit is structurally polar and has to attach to the filament in a particular orientation.

Bacterial initiation factor 2 binds to an initiator tRNA and controls the entry of that tRNA into the ribosome. IF2, bound to GTP, binds to the 30S P site. After associating with the 30S subunit, fMet-tRNAf binds to the IF2 then IF2 transfers the tRNA into the partial P site. When the 50S subunit joins, it hydrolyzes GTP to GDP and Pi, causing a conformational change in the IF2 that causes IF2 to release and allow the 70S subunit to form.

DNA polymerase subunit gamma (POLG or POLG1) is an enzyme that in humans is encoded by the POLG gene. Mitochondrial DNA polymerase is heterotrimeric, consisting of a homodimer of accessory subunits plus a catalytic subunit. The protein encoded by this gene is the catalytic subunit of mitochondrial DNA polymerase. Defects in this gene are a cause of progressive external ophthalmoplegia with mitochondrial DNA deletions 1 (PEOA1), sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO), Alpers-Huttenlocher syndrome (AHS), and mitochondrial neurogastrointestinal encephalopathy syndrome (MNGIE).

Protein phosphatase 1 regulatory subunit 12C is a protein that in humans is encoded by the PPP1R12C gene.

Replication protein A 32 kDa subunit is a protein that in humans is encoded by the RPA2 gene.

Replication protein A 14 kDa subunit is a protein that in humans is encoded by the RPA3 gene.

Mediator complex subunit 12 like (Med12L) is a protein that in humans is encoded by the MED12L gene.

CCR4-NOT transcription complex subunit 9 is a protein that in humans is encoded by the CNOT9 gene.

General transcription factor IIH subunit 5 is a protein that in humans is encoded by the GTF2H5 gene.

Dolichyl-diphosphooligosaccharide—protein glycosyltransferase subunit STT3B is an enzyme that in humans is encoded by the STT3B gene.

Protein phosphatase 1 regulatory subunit 7 is an enzyme that in humans is encoded by the PPP1R7 gene.

Transcription initiation factor TFIID subunit 4B is a protein that in humans is encoded by the TAF4B gene.

Replication protein A 30 kDa subunit is a protein that in humans is encoded by the RPA4 gene.

Trafficking protein particle complex subunit 4 is a protein that in humans is encoded by the TRAPPC4 gene.

Phosphoinositide 3-kinase regulatory subunit 5 is an enzyme that in humans is encoded by the PIK3R5 gene.

Gamma-aminobutyric acid receptor subunit delta is a protein that in humans is encoded by the GABRD gene.

Guanylate cyclase soluble subunit alpha-2 is an enzyme that in humans is encoded by the GUCY1A2 gene.

Protein phosphatase 1 regulatory subunit 17 is a protein that in humans is encoded by the PPP1R17 gene.

Protein phosphatase 1 regulatory subunit 14C is an enzyme that in humans is encoded by the PPP1R14C gene.

Transcription initiation factor TFIID subunit 3 is a protein that in humans is encoded by the TAF3 gene.

AP-3 complex subunit beta-2 is a protein that in humans is encoded by the AP3B2 gene.

Guanylate cyclase soluble subunit alpha-3 is an enzyme that in humans is encoded by the GUCY1A3 gene.

Pancreas transcription factor 1 subunit alpha is a protein that in humans is encoded by the PTF1A gene.

T-complex protein 1 subunit gamma is a protein that in humans is encoded by the CCT3 gene.

AP-3 complex subunit sigma-1 is a protein that in humans is encoded by the AP3S1 gene.

Guanylate cyclase soluble subunit beta-1 is an enzyme that in humans is encoded by the GUCY1B3 gene.

General transcription factor IIF subunit 1 is a protein that in humans is encoded by the GTF2F1 gene.

General transcription factor IIF subunit 2 is a protein that in humans is encoded by the GTF2F2 gene.

Protein phosphatase 1 regulatory subunit 3G is a protein that in humans is encoded by the PPP1R3G gene.

PAN3 poly(A) specific ribonuclease subunit is a protein that in humans is encoded by the PAN3 gene.

Platelet-derived growth factor subunit B is a protein that in humans is encoded by the PDGFB gene.

CCR4-NOT transcription complex, subunit 4 is a protein that in humans is encoded by the CNOT4 gene.

Phosphorylase b kinase regulatory subunit beta is an enzyme that in humans is encoded by the PHKB gene.

Rab3 GTPase-activating protein catalytic subunit is an enzyme that in humans is encoded by the RAB3GAP1 gene.

Small subunit processome component 20 homolog is a protein that in humans is encoded by the UTP20 gene.

Phosphatidylinositol 3-kinase regulatory subunit gamma is an enzyme, which in humans is encoded by the PIK3R3 gene.

AP-3 complex subunit sigma-2 is a protein that in humans is encoded by the AP3S2 gene.

T-complex protein 1 subunit beta is a protein that in humans is encoded by the CCT2 gene.

Dolichyl-diphosphooligosaccharide—protein glycosyltransferase subunit DAD1 is an enzyme that in humans is encoded by the DAD1 gene.

This gene encodes an alpha subunit of the heteromeric SEC61 complex, which also contains beta and gamma subunits.

T-complex protein 1 subunit zeta is a protein that in humans is encoded by the CCT6A gene.

AP-4 complex subunit beta-1 is a protein that in humans is encoded by the AP4B1 gene.

Protein geranylgeranyltransferase type I subunit beta is a protein that in humans is encoded by the PGGT1B gene.

Protein transport protein Sec61 subunit gamma is a protein that in humans is encoded by the SEC61G gene.

Protein phosphatase 1 regulatory subunit 14B is an enzyme that in humans is encoded by the PPP1R14B gene.

AP-4 complex subunit mu-1 is a protein that in humans is encoded by the AP4M1 gene.

Coumermycin A1 is an aminocoumarin. Its main target is the ATPase site of the DNA Gyrase GyrB subunit .

General transcription factor IIH subunit 1 is a protein that in humans is encoded by the GTF2H1 gene.

HAUS augmin-like complex subunit 3 is a protein that in humans is encoded by the HAUS3 gene.

In February 2018, 20 members of the ISIS Hunters (a 5th Corps subunit) died in a US airstrike.

Glutamate [NMDA] receptor subunit epsilon-1 is a protein that in humans is encoded by the GRIN2A gene.

Transcription initiation factor IIA subunit 1 is a protein that in humans is encoded by the GTF2A1 gene.

B subunit complexes labelled with fluorescent tags or subsequently targeted with antibodies can be used to identify rafts.

Also, Chk1 has been shown to be activated by the Scc1 subunit of the protein cohesin, in zygotes.

Splicing factor U2AF 65 kDa subunit is a protein that in humans is encoded by the U2AF2 gene.

These families are characterized by the sequence of their A (catalytic) subunit, as well as their catalytic ability.

Phosphatidylinositol 3-kinase regulatory subunit beta is an enzyme that in humans is encoded by the PIK3R2 gene.

AP-1 complex subunit mu-1 is a protein that in humans is encoded by the AP1M1 gene.

Nuclear transcription factor Y subunit beta is a protein that in humans is encoded by the NFYB gene.

T-complex protein 1 subunit alpha is a protein that in humans is encoded by the TCP1 gene.

Nuclear transcription factor Y subunit alpha is a protein that in humans is encoded by the NFYA gene.

AP-1 complex subunit gamma-1 is a protein that in humans is encoded by the AP1G1 gene.

Transcription initiation factor TFIID subunit 6 is a protein that in humans is encoded by the TAF6 gene.

AP-4 complex subunit epsilon-1 is a protein that in humans is encoded by the AP4E1 gene.

AP-4 complex subunit sigma-1 is a protein that in humans is encoded by the AP4S1 gene.

Protein phosphatase 1, regulatory subunit 27 is a protein in humans that is encoded by the PPP1R27 gene.

Splicing factor U2AF 35 kDa subunit is a protein that in humans is encoded by the U2AF1 gene.

General transcription factor IIH subunit 4 is a protein that in humans is encoded by the GTF2H4 gene.

Transcription initiation factor TFIID subunit 5 is a protein that in humans is encoded by the TAF5 gene.

ATP synthase F1 subunit alpha, mitochondrial is an enzyme that in humans is encoded by the ATP5F1A gene.

Transcription initiation factor TFIID subunit 10 is a protein that in humans is encoded by the TAF10 gene.

Chromatin assembly factor 1 subunit A is a protein that in humans is encoded by the CHAF1A gene.

Nuclear transcription factor Y subunit gamma is a protein that in humans is encoded by the NFYC gene.

T-complex protein 1 subunit epsilon is a protein that in humans is encoded by the CCT5 gene.

Cyclin-dependent kinases regulatory subunit 1 is a protein that in humans is encoded by the CKS1B gene.

Transcription factor IIIB 90 kDa subunit is a protein that in humans is encoded by the BRF1 gene.

Chromatin assembly factor 1 subunit B is a protein that in humans is encoded by the CHAF1B gene.

AP-3 complex subunit beta-1 is a protein that in humans is encoded by the AP3B1 gene.

AP-1 complex subunit mu-2 is a protein that in humans is encoded by the AP1M2 gene.

Glutamate [NMDA] receptor subunit epsilon-4 is a protein that in humans is encoded by the GRIN2D gene.

AP-3 complex subunit delta-1 is a protein that in humans is encoded by the AP3D1 gene.

Mitochondrial import receptor subunit TOM20 homolog is a protein that in humans is encoded by the TOMM20 gene.

AP-2 complex subunit alpha-2 is a protein that in humans is encoded by the AP2A2 gene.

Transcription initiation factor TFIID subunit 4 is a protein that in humans is encoded by the TAF4 gene.

Neuronal acetylcholine receptor subunit beta-4 is a protein that in humans is encoded by the CHRNB4 gene.

Origin recognition complex subunit 2 is a protein that is encoded by the ORC2 (ORC2L) gene in humans.

ATP synthase F1 subunit beta, mitochondrial is an enzyme that in humans is encoded by the ATP5F1B gene.

Transcription initiation factor TFIID subunit 12 is a protein that in humans is encoded by the TAF12 gene.

Trafficking protein particle complex subunit 3 is a protein that in humans is encoded by the TRAPPC3 gene.

Origin recognition complex subunit 3 is a protein that in humans is encoded by the ORC3 (ORC3L) gene.

KRR1 small subunit processome component homolog is a protein that in humans is encoded by the KRR1 gene.

AP-1 complex subunit sigma-2 is a protein that in humans is encoded by the AP1S2 gene.

T-complex protein 1 subunit eta is a protein that in humans is encoded by the CCT7 gene.

Origin recognition complex subunit 4 is a protein that in humans is encoded by the ORC4 (ORC4L) gene.

AP-1 complex subunit sigma-1A is a protein that in humans is encoded by the AP1S1 gene.

Glutamate [NMDA] receptor subunit epsilon-3 is a protein that in humans is encoded by the GRIN2C gene.

H/ACA ribonucleoprotein complex subunit 1 is a protein that in humans is encoded by the GAR1 gene.

Ribonuclease P/MRP protein subunit POP5 is an enzyme that in humans is encoded by the POP5 gene.

Ribonucleases P/MRP protein subunit POP1 is a protein that in humans is encoded by the POP1 gene.

Origin recognition complex subunit 6 is a protein that in humans is encoded by the ORC6 (ORC6L) gene.

Whole-residue octanol-scale hydropathy plot for the L-subunit of the photosynthetic reaction center of Rhodobacter sphaeroides.

General transcription factor IIH subunit 2 is a protein that in humans is encoded by the GTF2H2 gene.

HAUS augmin-like complex subunit 1 is a protein that in humans is encoded by the HAUS1 gene.

NEDD8-activating enzyme E1 regulatory subunit is a protein that in humans is encoded by the NAE1 gene.

2-Oxoisovalerate dehydrogenase subunit beta, mitochondrial is an enzyme that in humans is encoded by the BCKDHB gene.

V-type proton ATPase subunit H is an enzyme that in humans is encoded by the ATP6V1H gene.

Origin recognition complex subunit 5 is a protein that in humans is encoded by the ORC5 (ORC5L) gene.

Transcription initiation factor TFIID subunit 13 is a protein that in humans is encoded by the TAF13 gene.

Phosphatidylinositol 3-kinase regulatory subunit alpha is an enzyme that in humans is encoded by the PIK3R1 gene.

Decaprenyl-diphosphate synthase subunit 2 (PDSS2) is a protein that in humans is encoded by the PDSS2 gene.

It has been theorized that they may be the endogenous ligands of the subunit and that they may competitively antagonize the effects of gabapentinoids. In accordance, while gabapentinoids like pregabalin and gabapentin have nanomolar affinities for the α2δ subunit, their potencies in vivo are in the low micromolar range, and competition for binding by endogenous L-amino acids has been said to likely be responsible for this discrepancy. Pregabalin was found to possess 6-fold higher affinity than gabapentin for α2δ subunit-containing VDCCs in one study. However, another study found that pregabalin and gabapentin had similar affinities for the human recombinant α2δ-1 subunit (Ki = 32 nM and 40 nM, respectively).

An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. As a component of alpha ring, proteasome subunit alpha type-4 contributes to the formation of heptameric alpha rings and substrate entrance gate. Importantly, this subunit plays an critical role in the assembly of 19S base and 20S. In a study using Saccharomyces cerevisiae proteasome core particle 20S and regulatory particle 19S (similar to human proteasome) base component to delineate the binding process between 19S and 20S, evidences showed that one 19S subunit, Rpt6, can insert its tail into the pocket formed by alpha2 and alpha3 subunit (based on systematic nomenclature), facilitating the complex formation between 20S and 19S base component.

An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. As a component of alpha ring, Proteasome subunit alpha type-2 contributes to the formation of heptameric alpha rings and substrate entrance gate. Importantly, alpha2 subunit plays an critical role in the assembly of 19S base and 20S. In a study using Saccharomyces cerevisiae proteasome core particle 20S and regulatory particle 19S (similar to human proteasome) base component to delineate the binding process between 19S and 20S, evidences showed that one 19S subunit, Rpt6, can insert its tail into the pocket formed by alpha2 and alpha3 subunit, facilitating the complex formation between 20S and 19S base component.

The RNA-dependent RNA polymerase that replicates both the positive and negative RNA strands is a complex of four proteins: the catalytic beta subunit (replicase, ) is encoded by the phage, while the other three subunits are encoded by the bacterial genome: alpha subunit (ribosomal protein S1), gamma subunit (EF-Tu), and delta subunit (EF-Ts). The structure of the Qbeta RNA replicase has been solved (). The two EF proteins serve as a chaperone for both the replicase and the RNA product. In fact, pure Qbeta polymerase is not soluble enough to be produced in large quantities, and a fusion protein constructed from the replicase and the two EF subunits is usually used instead.

The role of the BAALC gene causing leukemia in immature acute leukemic cells has been found by knocking out the function of BAALC gene using hairpin (stem loop) RNA in a human leukemia cell line KG1a. The result of knocking out BAALC expression is a decrease in uncontrolled cell growth and an increase in programmed cell death. The BAALC protein isoform 1-6-8, has been found to interact and associate with the CAMKII alpha subunit and not with the beta subunit. The interaction with the CAMKII alpha subunit is in the CAMKII protein's regulatory region and near the autophosphorylation site, this suggested a regulatory function of the 1-6-8 isoform on the alpha subunit.

The F- and V-ATPases all contain rotary motors, one that drives proton translocation across the membrane and one that drives ATP synthesis/hydrolysis. In F-ATPases, the flux of protons through the ATPase channel drives the rotation of the C subunit ring, which in turn is coupled to the rotation of the F1 complex gamma subunit rotor due to the permanent binding between the gamma and epsilon subunits of F1 and the C subunit ring of Fo. The sequential protonation and deprotonation of Asp61 of subunit C is coupled to the stepwise movement of the rotor. In V-ATPases, there are three proteolipid subunits (c, c′ and c′′) that form part of the proton-conducting pore, each containing a buried glutamic acid residue that is essential for proton transport. In a recent study c-subunit has been indicated as a critical component of the mitochondrial permeability transition pore.

The molecular weight of CdtB ranges from 28 kDa to 29 kDa, depending on the species. As the active subunit, CdtB is termed the "A" subunit according to the AB toxin model. This confusing nomenclature is due to the naming of the toxin's subunits before their individual functions were understood.

The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (the HUGO-approved official symbol = PIK3CA; HGNC ID, HGNC:8975), also called p110α protein, is a class I PI 3-kinase catalytic subunit. The human p110α protein is encoded by the PIK3CA gene. Its role was uncovered by molecular pathological epidemiology (MPE).

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 8 is an enzyme that in humans is encoded by the NDUFA8 gene. The NDUFA8 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 6 is an enzyme that in humans is encoded by the NDUFA6 gene. The NDUFA6 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

Gamma-aminobutyric acid receptor subunit rho-2 is a protein that in humans is encoded by the GABRR2 gene. GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA receptors, which are ligand-gated chloride channels. GABRR2 is a member of the rho subunit family.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 5 is an enzyme that in humans is encoded by the NDUFA5 gene. The NDUFA5 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

The protein encoded by this gene is a subunit of the TRAPP (transport protein particle) tethering complex, which functions in intracellular vesicle trafficking. This subunit is involved in early stage endoplasmic reticulum-to-Golgi vesicle transport. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Jan 2013].

The ICAM binding site is on the alpha subunit. The general binding region of the alpha subunit is the I-domain. Due to the presence of a divalent cation site in the I-domain, the specific binding site is often referred to as the metal-ion dependent adhesion site (MIDAS).

Western blot and protein analysis were conducted to determine the relative amounts of VGCC subunit expression. α1C, α1D, and α2/δ1 subunits showed an increase of expression after sustained ethanol exposure. However, the β4 subunit showed a decrease. Furthermore, α1A, α1B, and α1F subunits did not alter in their relative expression.

It is present in 35% of all GABA-A receptors being the fourth most abundant subunit next to GABRA1 and various beta subunits. Like all subunits, it is made from structurally distinct proteins. The presence of this subunit causes an easier binding of benzodiazepine which is a category of psychoactive drugs.

Thus, Proteasomal ubiquitin receptor ADRM1 (Rpn13) is an important component of forming the base subcomplex of 19S regulatory particle. Traditional view of Rpn13 is that it is rather an associating partner of proteasome complex than a constitutive subunit. However, emerging evidences suggested that Rpn13 is a novel subunit of 19S.

The substrate is coordinated to the zinc and this enzyme has two zinc atoms per subunit. One is the active site, which is involved in catalysis. In the active site, the ligands are Cys-46, Cys-174, His-67, and one water molecule. The other subunit is involved with structure.

Schematic structure of MET protein MET is a receptor tyrosine kinase (RTK) that is produced as a single- chain precursor. The precursor is proteolytically cleaved at a furin site to yield a highly glycosylated extracellular α-subunit and a transmembrane β-subunit, which are linked together by a disulfide bridge.

Phosphorylase b kinase regulatory subunit alpha, skeletal muscle isoform is an enzyme that in humans is encoded by the PHKA1 gene. It is the muscle isoform of Phosphorylase kinase (PhK). The PHKA1 gene encodes the alpha subunit of muscle phosphorylase kinase (EC 2.7.1.38), a key regulatory enzyme of glycogen metabolism.

Their assembly into a complex leads to structural changes in both subunits resulting in reciprocal activation. There are two main mechanisms for intersubunit communication. First, the COMM domain of the β-subunit and the α-loop2 of the α-subunit interact. Additionally, there are interactions between the αGly181 and βSer178 residues.

Integrins function as the major cell receptor for extracellular matrix protein. These receptors comprise an α and β transmembrane subunit, which are noncovalently bound. Collagen binding is primarily provided by integrins α1β1, α2β1, α10β1 and α11β1. Integrin α1β1 binds to collagen via the MIDAS motif in the α subunit I domain.

In addition there is a fourth, so-called δ-subunit, that shares considerable sequence similarity with the α-subunit and can form a functional ion-channel together with the β- and γ-subunits. Such δ-, β-, γ-ENaC appear in pancreas, testes, lung, and ovaries. Their function is yet unknown.

There are seven, total enzymatic reactions in fatty acid synthesis. These reactions include: activation, priming, four reactions in elongation, and termination. Five these reactions are performed in the beta subunit and two reactions are performed in the alpha subunit. The 3D protein structure of the enzyme can be found here:PDB.

The A subunit is the only one that can be expressed alone and forms homomers with a very low single channel conductance of 0.6pS. When combined with the B subunit and expressed as a heteromer, the single channel conductance increases immensely. Alternatively spliced transcript variants encoding different isoforms have been identified.

The human protein 26S protease regulatory subunit 7 is 48.6kDa in size and composed of 433 amino acids. The calculated theoretical pI of this protein is 526S protease regulatory subunit 5.71. One expression isoform is generated by alternative splicing, in which 1–137 of the amino acid sequence is missing.

Calcium-activated potassium channel subunit alpha-1 also known as large conductance calcium-activated potassium channel, subfamily M, alpha member 1 (KCa1.1), or BK channel alpha subunit, is a voltage gated potassium channel encoded by the KCNMA1 gene and characterized by their large conductance of potassium ions (K+) through cell membranes.

The human protein 26S protease regulatory subunit 4 is 49kDa in size and composed of 440 amino acids. The calculated theoretical pI of this protein is 526S protease regulatory subunit 5.68. One expression isoform is generated by alternative splicing, in which 1-73 of the amino acid sequence is missing.

Argininosuccinate synthetase is a homotetramer, with each subunit consisting of 412 residues. The interfaces between subunits contain a number of salt bridges and hydrogen bonds, and the C-terminus of each subunit is involved in oligomerization by interacting with the C-termini and nucleotide-binding domains of the other subunits.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 13 is an enzyme that in humans is encoded by the NDUFA13 gene. The NDUFA13 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

COP9 signalosome complex subunit 3 is a protein that in humans is encoded by the COPS3 gene. It encodes a subunit of the COP9 signalosome. The protein encoded by this gene possesses kinase activity that phosphorylates regulators involved in signal transduction. It phosphorylates I-kappa-B-alpha, p105, and c-Jun.

Gamma-aminobutyric acid receptor subunit rho-1 is a protein that in humans is encoded by the GABRR1 gene. GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA receptors, which are ligand-gated chloride channels. GABRR1 is a member of the rho subunit family.

Interleukin-7 receptor subunit alpha (IL7R-α) also known as CD127 (Cluster of Differentiation 127) is a protein that in humans is encoded by the IL7R gene. IL7R-α is a type I cytokine receptor and is a subunit of the functional Interleukin-7 receptor and Thymic Stromal Lymphopoietin (TSLP) receptors.

Genetic knockouts of nicotinic receptor subunit β2 in mice resulted in a lack of conditioned place preference.Walters, L., Brown, S., Changeux, J., Martine, B., & Damaj, M.I. (2006). The β2 but not α7 subunit of the nicotinic acetylcholine receptor is required for nicotine-conditioned place preference in mice. Psychopharmacology, 184, 339-344.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 3 is a protein that in humans is encoded by the NDUFA3 gene. The NDUFA3 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

It is thought that Var1 plays a role in the early steps of small subunit assembly and is required for the incorporation of at least one ribosomal protein. It is important for mitochondrial translational initiation, since it requires the interaction between the small ribosomal subunit and the message-specific translation factors.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 7 is an enzyme that in humans is encoded by the NDUFA7 gene. The NDUFA7 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain.

The ribosome binding site of the alx gene is now exposed and the 30s subunit is allowed to bind.

FixK1 mutants are unable to respire from nitrogen due to a defective catatylic copper subunit (Cu-z) in nosRZDFYLX.

DNA-directed RNA polymerase III subunit RPC5 is an enzyme that in humans is encoded by the POLR3E gene.

Mitochondrial import inner membrane translocase subunit Tim23 is an enzyme that in humans is encoded by the TIMM23 gene.

Cleavage and polyadenylation specificity factor subunit 7 is a protein that in humans is encoded by the CPSF7 gene.

RNA, 5S cluster 1, also known as RN5S1@, is a human gene encoding the 5S subunit of ribosomal RNA.

Mitochondrial import inner membrane translocase subunit Tim22 is an enzyme that in humans is encoded by the TIMM22 gene.

NADH dehydrogenase [ubiquinone] 1 subunit C1, mitochondrial is an enzyme that in humans is encoded by the NDUFC1 gene.

Activating signal cointegrator 1 complex subunit 2 is a protein that in humans is encoded by the ASCC2 gene.

Platelet-activating factor acetylhydrolase IB subunit beta is an enzyme that in humans is encoded by the PAFAH1B2 gene.

DNA-directed RNA polymerase I subunit RPA1 is an enzyme that in humans is encoded by the POLR1A gene.

60S ribosome subunit biogenesis protein NIP7 homolog is a protein that in humans is encoded by the NIP7 gene.

Set1/Ash2 histone methyltransferase complex subunit ASH2 is an enzyme that in humans is encoded by the ASH2L gene.

DNA-directed RNA polymerase I subunit RPA34 is an enzyme that in humans is encoded by the CD3EAP gene.

DNA-directed RNA polymerase III subunit RPC6 is an enzyme that in humans is encoded by the POLR3F gene.

Cleavage and polyadenylation specificity factor subunit 3 is a protein that in humans is encoded by the CPSF3 gene.

V-type proton ATPase subunit G 3 is an enzyme that in humans is encoded by the ATP6V1G3 gene.

Mitochondrial import inner membrane translocase subunit Tim13 is an enzyme that in humans is encoded by the TIMM13 gene.

It acts a protein synthesis inhibitor and its site of action is the 50S subunit of the bacterial ribosome.

DNA-directed RNA polymerase I subunit RPA2 is an enzyme that in humans is encoded by the POLR1B gene.

Voltage-gated potassium channel subunit beta-2 is a protein that in humans is encoded by the KCNAB2 gene.

ARID2 is a subunit of the PBAF chromatin-remodeling complex, which facilitates ligand-dependent transcriptional activation by nuclear receptors.

Gamma-aminobutyric acid receptor subunit alpha-3 is a protein that in humans is encoded by the GABRA3 gene.

DNA-directed RNA polymerase I subunit RPA12 is an enzyme that in humans is encoded by the ZNRD1 gene.

Cleavage and polyadenylation specificity factor subunit 6 is a protein that in humans is encoded by the CPSF6 gene.

Guanine nucleotide-binding protein subunit alpha-13 is a protein that in humans is encoded by the GNA13 gene.

DNA-directed RNA polymerase III subunit RPC3 is an enzyme that in humans is encoded by the POLR3C gene.

Activating signal cointegrator 1 complex subunit 3 is a protein that in humans is encoded by the ASCC3 gene.

Serine/threonine-protein phosphatase 6 catalytic subunit is an enzyme that in humans is encoded by the PPP6C gene.

Mitochondrial import inner membrane translocase subunit TIM44 is an enzyme that in humans is encoded by the TIMM44 gene.

Platelet-activating factor acetylhydrolase IB subunit gamma is an enzyme that in humans is encoded by the PAFAH1B3 gene.

V-type proton ATPase subunit E 2 is an enzyme that in humans is encoded by the ATP6V1E2 gene.

In E. coli and other bacteria, holC is a gene that encodes the chi subunit of DNA polymerase III.

In E. coli and other bacteria, holD is a gene that encodes the psi subunit of DNA polymerase III.

In E. coli and other bacteria, holE is a gene that encodes the theta subunit of DNA polymerase III.

LIFR also known as CD118 (Cluster of Differentiation 118), is a subunit of a receptor for leukemia inhibitory factor.

It is bacteriostatic and acts by inhibiting bacterial protein synthesis via binding with the 50S subunit of the ribosome.

N(alpha)-acetyltransferase 35, NatC auxiliary subunit is a protein in humans that is encoded by the NAA35 gene.

Guanine nucleotide-binding protein subunit alpha-12 is a protein that in humans is encoded by the GNA12 gene.

High affinity immunoglobulin epsilon receptor subunit beta is a protein that in humans is encoded by the MS4A2 gene.

Nuclear factor NF-kappa-B p100 subunit is a protein that in humans is encoded by the NFKB2 gene.

This gene encodes the E1 beta subunit. Mutations in this gene are associated with pyruvate dehydrogenase E1-beta deficiency.

Interleukin-12 subunit alpha (IL-12 p35) is a protein that in humans is encoded by the IL12A gene.

The A subunit is then able to use its catalytic machinery to take over the host cell's regular functions.

DNA-directed RNA polymerase II subunit RPB3 is an enzyme that in humans is encoded by the POLR2C gene.

Gamma-aminobutyric acid receptor subunit gamma-2 is a protein that in humans is encoded by the GABRG2 gene.

26S proteasome non-ATPase regulatory subunit 5 is an enzyme that in humans is encoded by the PSMD5 gene.

26S proteasome non-ATPase regulatory subunit 13 is an enzyme that in humans is encoded by the PSMD13 gene.

26S proteasome non-ATPase regulatory subunit 12 is an enzyme that in humans is encoded by the PSMD12 gene.

26S proteasome non-ATPase regulatory subunit 11 is an enzyme that in humans is encoded by the PSMD11 gene.

26S proteasome non-ATPase regulatory subunit 8 is an enzyme that in humans is encoded by the PSMD8 gene.

Translation initiation factor eIF-2B subunit epsilon is a protein that in humans is encoded by the EIF2B5 gene.

26S proteasome non-ATPase regulatory subunit 6 is an enzyme that in humans is encoded by the PSMD6 gene.

Gamma-aminobutyric acid receptor subunit beta-2 is a protein that in humans is encoded by the GABRB2 gene.

26S proteasome non-ATPase regulatory subunit 9 is an enzyme that in humans is encoded by the PSMD9 gene.

26S proteasome non-ATPase regulatory subunit 3 is an enzyme that in humans is encoded by the PSMD3 gene.

This gene encodes a small subunit common to both calpain I and II and is associated with myotonic dystrophy.

Translation initiation factor eIF-2B subunit beta is a protein that in humans is encoded by the EIF2B2 gene.

Sodium/potassium-transporting ATPase subunit alpha-3 is an enzyme that in humans is encoded by the ATP1A3 gene.

Translation initiation factor eIF-2B subunit alpha is a protein that in humans is encoded by the EIF2B1 gene.

Calcium-activated potassium channel subunit beta-1 is a protein that in humans is encoded by the KCNMB1 gene.

Gamma-aminobutyric acid receptor subunit beta-1 is a protein that in humans is encoded by the GABRB1 gene.

Translation initiation factor eIF-2B subunit delta is a protein that in humans is encoded by the EIF2B4 gene.

Translation initiation factor eIF-2B subunit gamma is a protein that in humans is encoded by the EIF2B3 gene.

The phylogeny of the Sternorrhyncha, inferred from analysis of small subunit (18S) ribosomal RNA, is shown in the cladogram.

Cleavage and polyadenylation specificity factor subunit 2 is a protein that in humans is encoded by the CPSF2 gene.

Differences in the ligand binding pocket allow for the development of moderately subunit-selective kainate receptor agonists and antagonists.

The ATP5MC1 gene is one of three human paralogs that encode membrane subunit c of the mitochondrial ATP synthase.

ATP synthase-coupling factor 6, mitochondrial is an enzyme subunit that in humans is encoded by the ATP5PF gene.

Serine/threonine-protein phosphatase 4 catalytic subunit is an enzyme that in humans is encoded by the PPP4C gene.

DNA-directed RNA polymerase I subunit RPA49 is an enzyme that in humans is encoded by the POLR1E gene.

Transducin is activated by metarhodopsin II, a conformational change in rhodopsin caused by the absorption of a photon by the rhodopsin moiety retinal. The light causes isomerization of retinal from 11-cis to all-trans. Isomerization causes a change in the opsin to become metarhodopsin II. When metarhodopsin activates transducin, the guanosine diphosphate (GDP) bound to the α subunit (Tα) is exchanged for guanosine triphosphate (GTP) from the cytoplasm. The α subunit dissociates from the βγ subunits (Tβγ.) Activated transducin α-subunit activates cGMP phosphodiesterase.

AP complexes are heterotetramers composed of two large subunits (adaptins), a medium subunit (mu) and a small subunit (sigma). For example, in AP1 these subunits are gamma-1-adaptin, beta-1-adaptin, mu-1 and sigma-1, while in AP2 they are alpha-adaptin, beta-2-adaptin, mu-2 and sigma-2. Each subunit has a specific function. Adaptins recognise and bind to clathrin through their hinge region (clathrin box), and recruit accessory proteins that modulate AP function through their C-terminal ear (appendage) domains.

The PSST subunit encoded by the NDUSF7 gene is one of over 40 subunits involved in the transfer of electrons from NADH to ubiquinone. Specifically, it is thought that the PSST subunit directly couples electron transfer between the iron- sulfur cluster N2 and ubiquinone, along with ubiquinone-binding ND1. Functional evidence for the importance of PSST has been garnered from mutational studies in the obligate aerobic yeast, Yarrow lipolytic, which elucidated a central role in proton translocation that was reduced in mutant forms of the subunit.

Positive allosteric modulation (also known as allosteric activation) occurs when the binding of one ligand enhances the attraction between substrate molecules and other binding sites. An example is the binding of oxygen molecules to hemoglobin, where oxygen is effectively both the substrate and the effector. The allosteric, or "other", site is the active site of an adjoining protein subunit. The binding of oxygen to one subunit induces a conformational change in that subunit that interacts with the remaining active sites to enhance their oxygen affinity.

Phosphorylase b kinase gamma catalytic chain, testis/liver isoform is an enzyme that in humans is encoded by the PHKG2 gene. The PHKG2 gene provides instructions for making one piece, the gamma subunit, of the phosphorylase b kinase enzyme. This enzyme is made up of 16 subunits, four each of the alpha, beta, gamma, and delta subunits. (Each subunit is produced from a different gene.) The gamma subunit performs the function of phosphorylase b kinase enzyme, and the other subunits help regulate its activity.

The protein encoded by the KCNMB2 gene is an auxiliary beta subunit which influences the calcium sensitivity of BK currents and, following activation of BK current, causes persistent inactivation. The subunit encoded by the KCNMB2 gene is expressed in various endocrine cells, including pancreas and adrenal chromaffin cells. It is also found in the brain, including the hippocampus. The KCNMB2 gene is homologous to three other genes found in mammalian genomes: KCNMB1 (found primarily in smooth muscle), KCNMB3, and KCNMB4 (the primary brain BK auxiliary subunit).

Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 40S subunit and a member of the S14P family of ribosomal proteins. The protein, which contains a C2-C2 zinc finger-like domain that can bind to zinc, can enhance the tumor suppressor activity of Ras-related protein 1A (KREV1).

There are two binding sites on heteromeric nAChRs; to stabilize the open form of nAChRs, both binding sites must be occupied by agonist, such as nicotine or ACh. The ACh binding site of nAChR is made up by six loops, termed A–F. The A, B and C loops of the binding site are part of the α subunit and are the principal components of the binding site. The adjacent subunit to the α subunit (γ, δ, ε or β) contains the D, E and F loops.

The luteinizing hormone beta subunit is encoded by a single gene in all mammals. In primates, this gene is located within a cluster that arose through gene duplication, and also includes multiple redundant genes encoding the beta subunit of chorionic gonadotropin as well as several nonfunctional pseudogenes. In humans these are contiguous on chromosome 19q13.3. In equids the beta subunit polypeptides of luteinizing hormone and chorionic gonadotropin are identical in sequence, differing only in their carbohydrate side-chains, and are the product of a single gene.

This round is decided by the votes of 99 dancers. Round 8: Subunit Themes Each individual mentor has chosen a theme, making it 4 themes. Each team must create a subunit to dance to each theme, no subunit can have the same number of members. The themes given are ‘It’s just strong’, ‘Time control’, ‘Pink’ and ‘Butterfly Effect’. This round is decided by the votes of 99 dancers. The total number of votes throughout the 4 rounds are counted. The team with more overall votes win.

The peptide binding domain spans residues 140-215 of the α subunit, and consists of a concave surface lined with multiple tyrosine residues which interact favorably with the proline-rich substrate. The active site consists of Fe2+ bound to two histidine residues and one aspartate residue, a characteristic shared by most 2-oxoglutarate-dependent dioxygenases. The 55 kDa β subunit is responsible for the enzyme’s localization to and retention in the endoplasmic reticulum. This subunit is identical to the enzyme known as protein disulfide isomerase.

Rusticyanin is thought to shuttle electrons from high molecular weight cytochrome via cytochrome c552 to cytochrome oxidase. Predicted functional partners include coxD (cytochrome c oxidase, aa3-type, subunit IV, 64 amino acids), coxC (cytochrome c oxidase, aa3-type, subunit III, 184 amino acids), ctaB (protoheme IX farnesyltransferase), Cyc2 (cytochrome c, 485 amino acids), AFE_3142 (major facilitator family transporter, 397 amino acids), coxA (cytochrome c oxidase, aa3-type, subunit I, 627 amino acids), Cyc1 (cytochrome c552, 230 amino acids), and AFE_3141 (rrf2 family protein, 146 amino acids).

Protein phosphatase 1 regulatory subunit 12A is an enzyme that in humans is encoded by the PPP1R12A gene. Myosin phosphatase target subunit 1, which is also called the myosin-binding subunit of myosin phosphatase, is one of the subunits of myosin phosphatase. Myosin phosphatase regulates the interaction of actin and myosin downstream of the guanosine triphosphatase Rho. The small guanosine triphosphatase Rho is implicated in myosin light chain (MLC) phosphorylation, which results in contraction of smooth muscle and interaction of actin and myosin in nonmuscle cells.

In response to cellular metabolic stresses, AMPK is activated, and thus phosphorylates and inactivates acetyl-CoA carboxylase (ACC) and beta- hydroxy beta-methylglutaryl-CoA reductase (HMGCR), key enzymes involved in regulating de novo biosynthesis of fatty acid and cholesterol. This subunit may be a positive regulator of AMPK activity. The myristoylation and phosphorylation of this subunit have been shown to affect the enzyme activity and cellular localization of AMPK. This subunit may also serve as an adaptor molecule mediating the association of the AMPK complex.

This gene encodes one of seven subunits of the human Arp2/3 protein complex. This subunit is a member of the SOP2 family of proteins and is most similar to the protein encoded by gene ARPC1A. The similarity between these two proteins suggests that they both may function as p41 subunit of the human Arp2/3 complex that facilitates branching of actin filaments in cells. Isoforms of the p41 subunit may adapt the functions of the complex to different cell types or developmental stages.

CDK5 regulatory subunit-associated protein 3 is a protein that in humans is encoded by the CDK5RAP3 gene. Neuronal CDC2-like kinase, which is involved in the regulation of neuronal differentiation, is composed of a catalytic subunit, CDK5, and an activating subunit, p25NCK5A. The protein encoded by this gene binds to p25NCK5A and therefore may be involved in neuronal differentiation. The encoded protein, which may be a substrate of neuronal CDC2-like kinase, has also been found in vascular endothelial cells, where it mediates cell proliferation.

Voltage-dependent L-type calcium channel subunit beta-1 is a protein that in humans is encoded by the CACNB1 gene. The protein encoded by this gene belongs to the calcium channel beta subunit family. It plays an important role in the calcium channel by modulating G protein inhibition, increasing peak calcium current, controlling the alpha-1 subunit membrane targeting and shifting the voltage dependence of activation and inactivation. Alternative splicing occurs at this locus and three transcript variants encoding three distinct isoforms have been identified.

Cytochrome c oxidase subunit 8A (COX8A) is a protein that in humans is encoded by the COX8A gene. Cytochrome c oxidase 8A is a subunit of the cytochrome c oxidase complex, also known as Complex IV. Mutations in the COX8A gene have been associated with complex IV deficiency with Leigh syndrome and epilepsy.

Trifunctional enzyme subunit alpha, mitochondrial also known as hydroxyacyl- CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), alpha subunit is a protein that in humans is encoded by the HADHA gene. Mutations in HADHA have been associated with trifunctional protein deficiency or long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency.

Shows the five subunits that comprise the GABA-A receptor. GABRA2 is only one alpha subunit in the structure demonstrated with the color red.GABRA2 is one of the 16 distinct alpha subunits found for the GABA receptor. GABA-A has a pentametric form, with two alpha, two beta, and one gamma subunit.

Proteasomal ubiquitin receptor ADRM1 is a protein that in humans is encoded by the ADRM1 gene. Recent evidences on proteasome complex structure confirmed that the protein encoded by gene ADRM1, also known in yeast as 26S Proteasome regulatory subunit Rpn13 (systematic nomenclature for proteasome subunits), is a subunit of 19S proteasome complex.

The V1 domain contains the ATP catalytic site. The V0 domain consists of five different subunits: a, c, c', c and d. Additional isoforms of many of the V1 and V0 subunit proteins are encoded by multiple genes or alternatively spliced transcript variants. This gene encodes one of three G subunit proteins.

The α9 subunit forms a heterodimeric complex with a β1 subunit to form the α9β1 integrin. This integrin participates in cell adhesion with various ligands in the extracellular matrix (ECM), including extra domain A (EDA) fibronectin, tenascin-C, ADAMs, EMELIN1, osteopontin, and VEGF. α9β1 binding is independent of the RGD peptide sequence.

F-ATPases lacking this subunit generally transport sodium instead of protons. They are proposed to be called N-ATPases, since they seem to form a distinct group that is further apart from usual F-ATPases than A-ATPases are from V-ATPases. Human delta subunit of ATP synthase is coded by gene ATP5O.

ATP synthase F1 subunit epsilon, mitochondrial is an enzyme that in humans is encoded by the ATP5F1E gene. The protein encoded by ATP5F1E is a subunit of ATP synthase, also known as Complex V. Variations of this gene have been associated with mitochondrial complex V deficiency, nuclear 3 (MC5DN3) and Papillary Thyroid Cancer.

Most of the regulatory proteins have an ACT domain () and some of them have a NiKR-like C-terminal (). In bacteria (E. coli)), Acetolactate synthase consists of three pairs of isoforms. Each pair includes a large subunit, which is thought to be responsible for catalysis, and a small subunit for feedback inhibition.

In cultured hippocampal neurons, Tbr1 and calcium/calmodulin-dependent serine kinase (CASK) interact with CASK-interacting nucleosome assembly protein (CINAP) to modulate the expression of N-methyl-D-aspartic acid receptor subunit 2b (NR2b) by acting on its promoter region. Tbr1 is a transcriptional regulator of NR1, an essential subunit of NMDA receptors.

ArtAB toxin of Salmonella enterica has components similar to those found in two different families: the ArtA () subunit is homologous with pertussis toxin A, while the ArtB () subunit is homologous with subB as well as proteins found in other Salmonella strains. Under the categorize-by-A rule, it is a Ptx-family toxin.

The calpains, calcium-activated neutral proteases, are nonlysosomal, intracellular cysteine proteases. The mammalian calpains include ubiquitous, stomach-specific, and muscle-specific proteins. The ubiquitous enzymes consist of heterodimers with distinct large, catalytic subunits associated with a common small, regulatory subunit. This gene encodes the large subunit of the ubiquitous enzyme, calpain 2.

This gene encodes a subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. The product of this gene contains four conserved cysteines characteristic of an atypical zinc-binding domain. Like its counterpart in yeast, this subunit may be shared by the other two DNA-directed RNA polymerases.

The presynaptic acetylcholine secretion inhibition is caused by the phospholipase A2 activity of the CB subunit. The exact mechanism of presynaptic acetylcholine inhibition by Phospholipase A2 (PLA2) is not known. While the presynaptic effect is caused by the CB subunit, it is enhanced by the presence of the CA subunit.Cavalcante, Walter L.g.

The calpains, calcium-activated neutral proteases, are nonlysosomal, intracellular cysteine proteases. The mammalian calpains include ubiquitous, stomach-specific, and muscle-specific proteins. The ubiquitous enzymes consist of heterodimers with distinct large, catalytic subunits associated with a common small, regulatory subunit. This gene encodes the large subunit of the ubiquitous enzyme, calpain 1.

The first cDNA encoding the gamma subunit of ENaC was cloned and sequenced by Canessa et al. from rat mRNA. A year later, two independent groups reported the cDNA sequences of the beta- and gamma-subunits of the human ENaC. The complete coding sequence human γ subunit was reported by Saxena et al.

This gene encodes a subunit of the elongation factor-1 complex, which is responsible for the enzymatic delivery of aminoacyl tRNAs to the ribosome. This subunit contains an N-terminal glutathione transferase domain, which may be involved in regulating the assembly of multisubunit complexes containing this elongation factor and aminoacyl-tRNA synthetases.

IFNAR is composed of two subunits, IFNAR1 and IFNAR2. Each IFNAR subunit contains an N-terminal ligand binding domain, a transmembrane domain, and a C-terminal intracellular tail. IFNAR1 is the low affinity subunit, with four N-terminal subdomains. Binding to type I IFN is mediated by subdomains SD1, SD2 and SD3.

The β1 subunit aids recovery from inactivation, while β2 accelerates inactivation. The β subunits can also interfere with ball and chain domains by blocking their entry into the channel. This leads to persistent currents, caused by the continued influx of ions. The β3 subunit can increase persistent current in certain sodium channels.

The nature of the process can be depicted as follows: Consider a cluster with two subunits, A and B. Suppose an inner-valence electron is removed from subunit A. If the resulting (ionized) state is higher in energy than the double ionization threshold of subunit A then an intraatomic (intramolecular) process (autoionization, in the case of core ionization Auger decay) sets in. Even though the excitation is energetically not higher than the double ionization threshold of subunit A itself, it may be higher than the double ionization threshold of the cluster which is lowered due to charge separation. If this is the case, an interatomic (intermolecular) process sets in which is called ICD. During the ICD the excess energy of subunit A is used to remove (due to electronic correlation) an outer-valence electron from subunit B. As a result, a doubly ionized cluster is formed with a single positive charge on A and B. Thus, charge separation in the final state is a fingerprint of ICD.

Succinyl-CoA ligase [GDP-forming] subunit alpha, mitochondrial is an enzyme that in humans is encoded by the SUCLG1 gene.

Eukaryotic translation initiation factor 3 subunit C like is a protein that in humans is encoded by the EIF3CL gene.

A large number of V-ATPase subunit mutations have also been identified in a number of cancers, including follicular lymphomas.

KANSL3, or KAT8 regulatory NSL complex subunit 3 is a protein that in humans is encoded by the KANSL3 gene.

Mitochondrial import inner membrane translocase subunit Tim17-A is an enzyme that in humans is encoded by the TIMM17A gene.

Activating signal cointegrator 1 complex subunit 1 (ASCC1) is a protein that in humans is encoded by the ASCC1 gene.

Large neutral amino acids transporter small subunit 3 is a protein that in humans is encoded by the SLC43A1 gene.

Mediator of RNA polymerase II transcription subunit 25 is an enzyme that in humans is encoded by the MED25 gene.

5'-AMP-activated protein kinase subunit gamma-3 is an enzyme that in humans is encoded by the PRKAG3 gene.

This subunit may be involved in the regulation of genes by structural modulation of their chromatin, specifically in the brain.

Mediator of RNA polymerase II transcription subunit 8 is an enzyme that in humans is encoded by the MED8 gene.

This gene encodes a beta 3 subunit. A pseudogene exists for this gene, and it is located on chromosome 2.

Genetic sequences are highly conserved between Pacific and Atlantic populations. Relevant probe sequences for small subunit RNA can be found.

N-terminal acetyltransferase B complex catalytic subunit NAT5 is an enzyme that in humans is encoded by the NAT5 gene.

Eukaryotic translation initiation factor 3 subunit J (eIF3j) is a protein that in humans is encoded by the EIF3J gene.

Cleavage stimulation factor 64 kDa subunit, tau variant is a protein that in humans is encoded by the CSTF2T gene.

Actin-related protein 2/3 complex subunit 5 is a protein that in humans is encoded by the ARPC5 gene.

Actin-related protein 2/3 complex subunit 4 is a protein that in humans is encoded by the ARPC4 gene.

Eukaryotic translation initiation factor 3 subunit F (eIF3f) is a protein that in humans is encoded by the EIF3F gene.

Eukaryotic translation initiation factor 3 subunit D (eIF3d) is a protein that in humans is encoded by the EIF3D gene.

Large neutral amino acids transporter small subunit 2 is a protein that in humans is encoded by the SLC7A8 gene.

Mediator of RNA polymerase II transcription subunit 22 is an enzyme that in humans is encoded by the MED22 gene.

SUZ12 polycomb repressive complex 2 subunit pseudogene 1 is a protein that in humans is encoded by the SUZ12P1 gene.

The active sites are located between these subunits (subunit interfaces), each can bind to one SAM molecule at a time.

Mediator of RNA polymerase II transcription subunit 16 is an enzyme that in humans is encoded by the MED16 gene.

Serine/threonine-protein phosphatase 4 regulatory subunit 3B is an enzyme that in humans is encoded by the SMEK2 gene.

Eukaryotic translation initiation factor 3 subunit K (eIF3k) is a protein that in humans is encoded by the EIF3K gene.

PAB-dependent poly(A)-specific ribonuclease subunit 2 is an enzyme that in humans is encoded by the PAN2 gene.

In E. coli and other bacteria, holB is a gene that encodes the delta prime subunit of DNA polymerase III.

Congenital SSS can be due to mutations of the gene responsible for formation of Alpha subunit of sodium channel (SCN5A).

Guanine nucleotide-binding protein G(k) subunit alpha is a protein that in humans is encoded by the GNAI3 gene.

Serine/threonine-protein phosphatase 4 regulatory subunit 1 is an enzyme that in humans is encoded by the PPP4R1 gene.

Serine/threonine-protein phosphatase PP1-alpha catalytic subunit is an enzyme that in humans is encoded by the PPP1CA gene.

Gamma-aminobutyric acid (GABA) B receptor, 1 (GABAB1), is a G-protein coupled receptor subunit encoded by the GABBR1 gene.

DNA-directed RNA polymerase II subunit RPB11-a is an enzyme that in humans is encoded by the POLR2J gene.

Replication protein A 70 kDa DNA-binding subunit is a protein that in humans is encoded by the RPA1 gene.

Serine/threonine-protein phosphatase PP1-gamma catalytic subunit is an enzyme that in humans is encoded by the PPP1CC gene.

Eukaryotic translation initiation factor 2 subunit 1 (eIF2α) is a protein that in humans is encoded by the EIF2S1 gene.

Eukaryotic translation initiation factor 3 subunit E (eIF3e) is a protein that in humans is encoded by the EIF3E gene.

5'-AMP-activated protein kinase subunit gamma-2 is an enzyme that in humans is encoded by the PRKAG2 gene.

Calpain small subunit 1, also known as CAPN4, is a protein that in humans is encoded by the CAPNS1 gene.

Mediator of RNA polymerase II transcription subunit 24 is an enzyme that in humans is encoded by the MED24 gene.

Guanine nucleotide-binding protein G(z) subunit alpha is a protein that in humans is encoded by the GNAZ gene.

Phosphorylase b kinase regulatory subunit alpha, liver isoform is an enzyme that in humans is encoded by the PHKA2 gene.

V-type proton ATPase 16 kDa proteolipid subunit is an enzyme that in humans is encoded by the ATP6V0C gene.

Eukaryotic translation initiation factor 2 subunit 2 (eIF2β) is a protein that in humans is encoded by the EIF2S2 gene.

Actin-related protein 2/3 complex subunit 1B is a protein that in humans is encoded by the ARPC1B gene.

Eukaryotic translation initiation factor 3 subunit I (eIF3i) is a protein that in humans is encoded by the EIF3I gene.

5'-AMP-activated protein kinase subunit gamma-1 is an enzyme that in humans is encoded by the PRKAG1 gene.

Mediator of RNA polymerase II transcription subunit 21 is an enzyme that in humans is encoded by the MED21 gene.

Mediator of RNA polymerase II transcription subunit 23 is an enzyme that in humans is encoded by the MED23 gene.

Laminin subunit gamma-3 also known as LAMC3 is a protein that in humans is encoded by the LAMC3 gene.

Eukaryotic translation initiation factor 3 subunit G (eIF3g) is a protein that in humans is encoded by the EIF3G gene.

Eukaryotic translation initiation factor 2 subunit 3 (eIF2γ) is a protein that in humans is encoded by the EIF2S3 gene.

Eukaryotic translation initiation factor 3 subunit B (eIF3b) is a protein that in humans is encoded by the EIF3B gene.

Eukaryotic translation initiation factor 3 subunit C (eIF3c) is a protein that in humans is encoded by the EIF3C gene.

Eukaryotic translation initiation factor 3 subunit H (eIF3h) is a protein that in humans is encoded by the EIF3H gene.

Actin-related protein 2/3 complex subunit 2 is a protein that in humans is encoded by the ARPC2 gene.

This suggests that segments that protrude into, or interwind with, a neighbouring subunit may have a lower propensity to fold.

The 46-nucleotide overlap in the reading frames of the human mitochondrial genes MT-ATP6 and MT-ATP8. For each nucleotide triplet (square brackets), the corresponding amino acid is given (one-letter code), either in the +3 frame for MT-ATP6 (in blue) or in the +1 frame for MT-ATP8 (in red). MT-ATP6 (or ATP6) is a mitochondrial gene with the full name 'mitochondrially encoded ATP synthase membrane subunit 6' that encodes the ATP synthase Fo subunit 6 (or subunit/chain A). This subunit belongs to the Fo complex of the large, transmembrane F-type ATP synthase. This enzyme, which is also known as complex V, is responsible for the final step of oxidative phosphorylation in the electron transport chain.

Two units of 5,6-LAM (AdoCbl in yellow and PLP in orange) 5,6-LAM is an α2β2 tetramer. The structure of the alpha subunit is predominantly a PLP-binding TIM barrel domain, with several additional alpha-helices and beta-strands at the N and C termini. These helices and strands form an intertwined accessory clamp structure that wraps around the sides of the TIM barrel and extends up toward the Ado ligand of the Cbl cofactor, which is the beta subunit providing most of the interactions observed between the protein and the Ado ligand of the Cbl, suggesting that its role is mainly in stabilizing AdoCbl in the precatalytic resting state. The β subunit binds AdoCbl while the PLP directly binds to α subunit.