Mosaic evolution of prepropancreatic polypeptide

• Published in: The Journal of biological chemistry Vol. 261; no. 14; pp. 6156 - 6159
• Main Authors: Yamamoto, H, Nata, K, Okamoto, H
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 15.05.1986; American Society for Biochemistry and Molecular Biology
• Subjects: Amino Acid Sequence; Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Animals; Base Sequence; Biological and medical sciences; Deoxyribonucleases, Type II Site-Specific; DNA - analysis; DNA Restriction Enzymes - metabolism; Fundamental and applied biological sciences. Psychology; Humans; Male; Mosaicism; Pancreatic Polypeptide; Protein Precursors - genetics; Proteins; Rats; Rats, Inbred Strains; RNA, Messenger - analysis; Vertebrata; Mammalia; Rat; Animal; Biological evolution; Rodentia; Peptide hormone; Mosaicism; Primary structure; Langerhansian islet; Pancreas
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(19)84542-8

Pancreatic polypeptide, a 36-amino acid peptide hormone, is synthesized in pancreatic islets of Langerhans and acts as a regulator of pancreatic and gastrointestinal functions. We isolated cDNA clones encoding rat pancreatic polypeptide precursor from an islet cDNA library and determined their nucleic acid sequences. Rat pancreatic polypeptide was found to be flanked on the amino terminus by a putative signal peptide and on the carboxyl terminus by Gly-Lys-Arg followed by a 30-amino acid peptide. Nucleotide and amino acid sequences of the signal peptide and the pancreatic polypeptide of the rat were highly homologous to those of the human (Boel, E., Schwartz, T. W., Norris, K. E., and Fill, N. P. (1984) EMBO J. 3, 909-912). On the other hand, the rat carboxyl-terminal peptide differed markedly from the corresponding domain of the human precursor and did not contain any sequence similar to the icosapeptide, which has so far been known to be a second stable product from mammalian pancreatic polypeptide precursors (Schwartz, T. W., Hansen, H. F., Hakanson, R., Sundler, F., and Tager, H. S. (1984) Proc. Natl. Acad. Sci. U. S. A. 81, 708-712). The mosaicism of sequence conservation and divergence in prepropancreatic polypeptides may be a unique example in the evolution of prohormones.