Open AccessComplete amino acid sequence of a human pituitary glycopeptide: an important maturation product of pro-opiomelanocortin.
Author(s) -
Nabil G. Seidah,
Michel Chrétien
Publication year - 1981
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.78.7.4236
Subject(s) - glycopeptide , peptide sequence , biochemistry , amino acid , biology , proopiomelanocortin , cleavage (geology) , enzyme , pituitary gland , chemistry , hormone , gene , paleontology , fracture (geology) , antibiotics
A glycopeptide isolated in relatively large amounts from human pituitary glands was completely purified, and its sequence was determined. The primary sequence represents the NH2-terminal 76 amino acid residues of pro-opiomelanocortin (POMC). This important secretory product of POMC was shown to possess an interesting aldosterone-stimulating activity on a human adrenal aldosteronoma. It is O-glycosylated at Thr-45 and N-glycosylated at Asn-65. Only one sequence variation with the human genomic DNA was found. Furthermore, comparison with the other preferred cleavage sites of human POMC reveals that the pair of basic residues Lys-Arg represents the major sites of enzymatic maturation of this precursor molecule. This predicts a highly specific type of enzyme involved in the maturation of POMC in the anterior lobe of the human pituitary.