title: Identification and expression analysis of hepcidin-like antimicrobial peptides in bony fish.
abstract: Antimicrobial peptides play a crucial role as the first line of defense against invading pathogens. Several types of antimicrobial peptides have been isolated from fish, mostly of the cationic alpha-helical variety. Here, we present the cDNA sequences of five highly disulphide-bonded hepcidin-like peptides from winter flounder, Pseudopleuronectes americanus (Walbaum) and two from Atlantic salmon, Salmo salar (L.). These hepcidin-like molecules consist of a 24 amino acid signal peptide and an acidic propiece of 38-40 amino acids in addition to the mature processed peptide of 19-27 amino acids. Exhaustive data mining of GenBank with these sequences revealed that similar peptides are encoded in the genomes of Japanese flounder, rainbow trout, hybrid striped bass and medaka, indicating that they are widespread among fish. Southern hybridization analysis suggests that closely related hepcidin-like genes are present in other flatfish species, and that they exist as a multigene family clustered on the winter flounder genome. Hepcidin variants are differentially expressed during bacterial challenge, during larval development of P. americanus and in different tissues of adult fish.
authors.affiliation: Institute for Marine Biosciences, National Research Council, 1411 Oxford Street, Halifax, NS, Canada B3H 3Z1. susan.douglas@nrc.ca
authors.forename: Susan E
authors.initials: SE
authors.lastname: Douglas
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Gallant
authors.forename: Ryan S
authors.initials: RS
authors.lastname: Liebscher
authors.forename: Andrew
authors.initials: A
authors.lastname: Dacanay
authors.forename: Stephen C M
authors.initials: SC
authors.lastname: Tsoi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D001483:Base Sequence; D018076:DNA, Complementary; D005432:Flounder / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D005786:Gene Expression Regulation / Q000276:immunology; D018507:Gene Expression Regulation, Developmental; D064451:Hepcidins; D008969:Molecular Sequence Data; D009928:Organ Specificity; D020317:Salmo salar / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary; D064451:Hepcidins