title: Identification and characterization of a hepcidin from half-smooth tongue sole Cynoglossus semilaevis.
abstract: Hepcidin, an antimicrobial peptide, has a dual function including innate immunity and iron regulation. Here, based on the sequence of an EST database, we have isolated and characterized a hepcidin gene (referred to as CsHepcidin) from half-smooth tongue sole (Cynoglossus semilaevis). Analysis of the coding regions indicated CsHepcidin gene comprised 3 exons and 2 introns. The putative CsHepcidin showed a great similarity to other hepcidin orthologues, particularly with respect to its 24 aa signal peptide, typical RX(K/R)R motif and eight conserved cysteine residues in the mature cationic peptide. Phylogenic analysis indicated that CsHepcidin was a hepcidin 1-type peptide of acanthopterygians, with highly homologous with Solea senegalensis hepcidin. In C. semilaevis ontogeny, CsHepcidin mRNA was detected at a low level in unfertilized eggs, increased on 6 d after hatching, and decreased remarkably at metamorphic stage. CsHepcidin transcripts showed a constitutive basal expression in most of the tissues, especially in liver. Challenge with formalin-inactivated Vibrio anguillarum led to significantly up-regulations of CsHepcidin gene in liver, head kidney and spleen in time-dependent manners. Biological activity analysis showed that recombinant CsHEP exhibited direct antimicrobial activity against bacterial pathogens in vitro, particularly showed strong activity against the principal fish pathogens, V. anguillarum and Edwardsiella tarda. All these results suggest that CsHepcidin may be involved in the initial response to invasion of microbial pathogens. Further exploration to elucidate the role of CsHepcidin in iron regulation and embryogenesis in C. semilaevis are needed.
authors.affiliation: College of Marine Life Science, Ocean University of China, Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Qingdao, PR China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Wang
authors.forename: Xudong
authors.initials: X
authors.lastname: Liu
authors.forename: Liman
authors.initials: L
authors.lastname: Ma
authors.forename: Yan
authors.initials: Y
authors.lastname: Yu
authors.forename: Haiyang
authors.initials: H
authors.lastname: Yu
authors.forename: Shafi
authors.initials: S
authors.lastname: Mohammed
authors.forename: Guannan
authors.initials: G
authors.lastname: Chu
authors.forename: Linlin
authors.initials: L
authors.lastname: Mu
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000276:immunology* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001483:Base Sequence; D005393:Fish Diseases / Q000276:immunology* / Q000401:mortality; D005412:Flatfishes / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D064451:Hepcidins; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D014733:Vibrio; D014735:Vibrio Infections / Q000276:immunology / Q000401:mortality / Q000662:veterinary*
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D064451:Hepcidins