title: A novel proline rich bombesin-related peptide (PR-bombesin) from toad Bombina maxima.
abstract: A novel bombesin-related peptide was isolated from skin secretions of Chinese red belly toad Bombina maxima. Its primary structure was established as pGlu-Lys-Lys-Pro-Pro-Arg-Pro-Pro-Gln-Trp-Ala-Val-Gly-His-Phe-Met-NH(2.) The amino-terminal (N-terminal) 8-residue segment comprising four prolines and three basic residues is extensively different from bombesins from other Bombina species. The peptide was thus named proline rich bombesin (PR-bombesin). PR-bombesin was found to elicit concentration-dependent contractile effects in the rat stomach strip, with both increased potency and intrinsic activity as compared with those of [Leu(13)]bombesin. Analysis of different bombesin cDNA structures revealed that an 8 to 14- nucleotide fragment replacement in the peptide coding region (TGGGGAAT in the cDNAs of multiple bombesin forms from Bombina orientalis and CACCCCGGCCACCC in the cDNA of PR-bombesin) resulted in an unusual Pro-Pro-Arg-Pro-Pro motif in the N-terminal part of PR-bombesin.
authors.affiliation: Department of Animal Toxinology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223 Peoples Republic of, Yunnan, China.
authors.forename: Ren
authors.initials: R
authors.lastname: Lai
authors.forename: Hen
authors.initials: H
authors.lastname: Liu
authors.forename: Wen Hui
authors.initials: WH
authors.lastname: Lee
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura; D001483:Base Sequence; D001839:Bombesin / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D011392:Proline / Q000737:chemistry*; D011498:Protein Precursors / Q000235:genetics; D051381:Rats; D012867:Skin / Q000737:chemistry*; D013270:Stomach / Q000187:drug effects
chemical_list: D018076:DNA, Complementary; D011498:Protein Precursors; D011392:Proline; D001839:Bombesin