title: Two different types of hepcidins from the Japanese flounder Paralichthys olivaceus.
abstract: The cysteine-rich peptide hepcidin is known to be an antimicrobial peptide and iron transport regulator that has been found in both fish and mammals. Recently, we found two different types (designated Hep-JF1 and Hep-JF2) of hepcidin cDNA in the Japanese flounder, Paralichthys olivaceus, by expressed sequence tag analysis. The identity of amino acid sequences between Hep-JF1 and Hep-JF2 was 51%. The Hep-JF1 and Hep-JF2 genes both consist of three exons and two introns, and both exist as single copies in the genome. The predicted mature regions of Hep-JF1 and Hep-JF2 have six and eight Cys residues, respectively. The first Cys residue of Hep-JF1 was deleted and the second was replaced with Gly. The number and positions of Cys residues in Hep-JF2 are the same as they are in human Hep. Hep-JF1 is specifically expressed in liver while the expression of Hep-JF2 was detected from gill, liver, heart, kidney, peripheral blood leucocytes, spleen and stomach. Gene expression of Hep-JF1 in liver decreased during experimental iron (iron-dextran) overload. Expression of Hep-JF1 in liver was decreased by injecting fish with iron-dextran and increased by injecting lipopolysaccharide. Iron overload did not significantly affect expression of Hep-JF2 in liver but it did increase expression of Hep-JF2 in kidney. Lipopolysaccharide injection increased expression of Hep-JF2 in both liver and kidney. In liver, some cells expressed both Hep-JF1 and Hep-JF2 while some other cells expressed just one of them. Synthesized Hep-JF2 peptide showed antimicrobial activity, while synthesized Hep-JF1 peptide did not against several bacteria including fish-pathogenic bacteria used in this study.
authors.affiliation: Laboratory of Genome Science, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Konan, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Hirono
authors.forename: Jee-Youn
authors.initials: JY
authors.lastname: Hwang
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Ono
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Kurobe
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ohira
authors.forename: Reiko
authors.initials: R
authors.lastname: Nozaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Aoki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000494:pharmacology; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004912:Erythrocytes / Q000187:drug effects; D005432:Flounder / Q000235:genetics* / Q000378:metabolism; D018628:Gene Dosage; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D005880:Gills / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D064451:Hepcidins; D017403:In Situ Hybridization; D007505:Iron-Dextran Complex / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008099:Liver / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; C578702:HAMP protein, human; D064451:Hepcidins; D008070:Lipopolysaccharides; D020033:Protein Isoforms; D012333:RNA, Messenger; D007505:Iron-Dextran Complex