title: Identification of a new member of the GLWamide peptide family: physiological activity and cellular localization in cnidarian polyps.
abstract: KPNAYKGKLPIGLWamide, a novel member of the GLWamide peptide family, was isolated from Hydra magnipapillata. The purification was monitored with a bioassay: contraction of the retractor muscle of a sea anemone, Anthopleura fuscoviridis. The new peptide, termed Hym-370, is longer than the other GLWamides previously isolated from H. magnipapillata and another sea anemone, A. elegantissima. The amino acid sequence of Hym-370 is six residues longer at its N-terminal than a putative sequence previously deduced from the cDNA encoding the precursor protein. The new longer isoform, like the shorter GLWamides, evoked concentration-dependent muscle contractions in both H. magnipapillata and A. fuscoviridis. In contrast, Hym-248, one of the shorter GLWamide peptides, specifically induced contraction of the endodermal muscles in H. magnipapillata. This is the first case in which a member of the hydra GLWamide family (Hym-GLWamides) has exhibited an activity not shared by the others. Polyclonal antibodies were raised to the common C-terminal tripeptide GLWamide and were used in immunohistochemistry to localize the GLWamides in the tissue of two species of hydra, H. magnipapillata and H. oligactis, and one species of sea anemone, A. fuscoviridis. In each case, nerve cells were specifically labeled. These results suggest that the GLWamides are ubiquitous among cnidarians and are involved in regulating the excitability of specific muscles.
authors.affiliation: Physiological Laboratory, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Takahashi
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kobayakawa
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Muneoka
authors.forename: Yuko
authors.initials: Y
authors.lastname: Fujisawa
authors.forename: Shirou
authors.initials: S
authors.lastname: Mohri
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hatta
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shimizu
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Fujisawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Michiyo
authors.initials: M
authors.lastname: Takahara
authors.forename: Kensuke
authors.initials: K
authors.lastname: Yanagi
authors.forename: Osamu
authors.initials: O
authors.lastname: Koizumi
mesh_terms: D000577:Amides / Q000032:analysis; D000595:Amino Acid Sequence; D000818:Animals; D003063:Cnidaria / Q000166:cytology; D004305:Dose-Response Relationship, Drug; D006829:Hydra / Q000737:chemistry* / Q000166:cytology / Q000187:drug effects; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology*; D019151:Peptide Library
chemical_list: D000577:Amides; D009479:Neuropeptides; D019151:Peptide Library