Somatostatin, also known as growth hormone-inhibiting hormone (GHIH) or by several other names, is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with G protein-coupled somatostatin receptors and inhibition of the release of numerous secondary hormones. Somatostatin inhibits insulin and glucagon secretion.
Proprotein convertase 2 (PC2) also known as prohormone convertase 2 or neuroendocrine convertase 2 (NEC2) is a serine protease and proprotein convertase PC2, like proprotein convertase 1 (PC1), is an enzyme responsible for the first step in the maturation of many neuroendocrine peptides from their precursors, such as the conversion of proinsulin to insulin intermediates. To generate the bioactive form of insulin, a second step involving the removal of C-terminal basic residues is required; this step is mediated by carboxypeptidases E and/or D. PC2 plays only a minor role in the first step of insulin biosynthesis, but a greater role in the first step of glucagon biosynthesis compared to PC1. PC2 binds to the neuroendocrine protein named 7B2, and if this protein is not present, proPC2 cannot become enzymatically active. 7B2 accomplishes this by preventing the aggregation of proPC2 to inactivatable forms. The C-terminal domain of 7B2 also inhibits PC2 activity until it is cleaved into smaller inactive forms that lack carboxy-terminal basic residues. Thus, 7B2 is both an activator and an inhibitor of PC2. PC2 has been identified in a number of animals, including C. elegans.
The gastric inhibitory polypeptide receptor (GIP-R), also known as the glucose-dependent insulinotropic polypeptide receptor, is a protein that in humans is encoded by the GIPR gene.
Gonadotropin-releasing hormone receptor is a protein that in humans is encoded by the GNRHR gene.
Somatostatin receptor type 2 is a protein that in humans is encoded by the SSTR2 gene.
Somatostatin receptor type 5 is a protein that in humans is encoded by the SSTR5 gene.
Neuropeptides B/W receptor 1, also known as NPBW1 and GPR7, is a human protein encoded by the NPBWR1 gene. As implied by its name, it and related gene NPBW2 are transmembranes protein that bind Neuropeptide B (NPB) and Neuropeptide W (NPW), both proteins expressed strongly in parts of the brain that regulate stress and fear including the extended amygdala and stria terminalis. When originally discovered in 1995, these receptors had no known ligands and were called GPR7 and GPR8, but at least three groups in the early 2000s independently identified their endogenous ligands, triggering the name change in 2005.
Neuropeptides B/W receptor 2, also known as NPBW2, is a human protein encoded by the NPBWR2 gene.
Parathyroid hormone 2 receptor is a protein that in humans is encoded by the PTH2R gene.
Somatostatin receptor type 1 is a protein that in humans is encoded by the SSTR1 gene.
Shekel Somatostatin receptor type 3 is a protein that in humans is encoded by the SSTR3 gene.
Somatostatin receptor type 4 is a protein that in humans is encoded by the SSTR4 gene.
Neuropeptide FF receptor 2, also known as NPFF2 is a human protein encoded by the NPFFR2 gene.
Relaxin/insulin-like family peptide receptor 3, also known as RXFP3, is a human G-protein coupled receptor.
Endothelin-3 is a protein that in humans is encoded by the EDN3 gene.
Progonadoliberin-2 is a protein that in humans is encoded by the GNRH2 gene.
DNA-directed RNA polymerase III subunit RPC9 is an enzyme that in humans is encoded by the CRCP gene.
Early placenta insulin-like peptide is a protein that in humans is encoded by the INSL4 gene.
NPW is a gene that in humans encodes Neuropeptide W protein.
Tuberoinfundibular peptide of 39 residues is a protein that in humans is encoded by the PTH2 gene.
