Complete amino acid sequence of a human pituitary glycopeptide: an important maturation product of pro-opiomelanocortin.
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.
D000450:Aldosterone / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D005796:Genes; D006020:Glycopeptides / Q000235:genetics; D006801:Humans; D010446:Peptide Fragments; D010908:Pituitary Hormones, Anterior / Q000302:isolation & purification / Q000378:metabolism*; D011333:Pro-Opiomelanocortin; D011498:Protein Precursors / Q000378:metabolism*
D006020:Glycopeptides; D010446:Peptide Fragments; D010908:Pituitary Hormones, Anterior; D011498:Protein Precursors; D000450:Aldosterone; D011333:Pro-Opiomelanocortin