title: Pro-opiocortin processing in the pituitary: a model for neuropeptide biosynthesis.
abstract: The biosynthesis of alpha-MSH, beta-endorphin and ACTH in the pituitary is reviewed. These neuropeptides are synthesized from a common pro-protein, pro-opiomelanocortin. The pro-protein is cleaved intragranularly, at pairs of basic residues in the molecule to yield the respective peptide products. An unique, thiol protease (pro-opiocortin converting enzyme) and a carboxypeptidase B-like enzyme, both localized within pituitary secretory granules and having a pH optimum of 5-6, appear to be involved in the proteolytic processing of pro-opiomelanocortin.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000096:biosynthesis; D000818:Animals; D001921:Brain / Q000378:metabolism; D004723:Endorphins / Q000096:biosynthesis; D009074:Melanocyte-Stimulating Hormones / Q000096:biosynthesis; D051379:Mice; D008954:Models, Biological; D010447:Peptide Hydrolases / Q000494:pharmacology; D010902:Pituitary Gland / Q000378:metabolism*; D010908:Pituitary Hormones, Anterior / Q000096:biosynthesis*; D011333:Pro-Opiomelanocortin; D014176:Protein Biosynthesis; D011498:Protein Precursors / Q000096:biosynthesis*; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D010908:Pituitary Hormones, Anterior; D011498:Protein Precursors; D001615:beta-Endorphin; D011333:Pro-Opiomelanocortin; D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones; D010447:Peptide Hydrolases