Purification and characterization of galanin from the phylogenetically ancient fish, the bowfin (Amia calva) and dogfish (Scyliorhinus canicula).
Galanin was purified to near homogeneity from an extract of the stomachs of the holostean fish, the bowfin and the elasmobranch fish, the European common dogfish. Bowfin galanin contains an alpha'-amidated C-terminal residue and the primary structure of the peptide (GWTNL SAGYL LGPHA VDNHR SLNDK HGLA) shows only four amino acid substitutions (Val16-->Ile, Leu22-->Phe, Asn23-->His, and His26-->Tyr) compared with pig galanin. Dogfish galanin was isolated in a truncated form for which amino acid sequence was identical to residues (1-20) of bowfin galanin. The isolation of this fragment is indicative of processing at the site of a single arginyl residue, and an analogous peptide has been previously isolated from human intestine. The data demonstrate that peptides with close structural similarity to mammalian galanins are present in the gastrointestinal tracts of phylogenetically ancient fish.
Wang
Y
Y
Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178.
Conlon
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D004284:Dogfish; D005399:Fishes / Q000145:classification; D019004:Galanin; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000302:isolation & purification*; D010455:Peptides / Q000302:isolation & purification*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D013270:Stomach / Q000737:chemistry*; D014020:Tissue Extracts / Q000737:chemistry
D009479:Neuropeptides; D010455:Peptides; D014020:Tissue Extracts; D019004:Galanin