Cloning and expression of a hepcidin gene from a marine fish ( Pseudosciaena crocea) and the antimicrobial activity of its synthetic peptide

• Published in: Peptides (New York, N.Y. : 1980) Vol. 30; no. 4; pp. 638 - 646
• Main Authors: Wang, Ke-Jian, Cai, Jing-Jing, Cai, Ling, Qu, Hai-Dong, Yang, Ming, Zhang, Min
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.04.2009; Elsevier
• Subjects: Aeromonas hydrophila; Aeromonas hydrophila - drug effects; Amino Acid Sequence; Animals; Anti-Infective Agents - chemistry; Anti-Infective Agents - pharmacology; Antimicrobial activity; Antimicrobial Cationic Peptides - chemistry; Antimicrobial Cationic Peptides - genetics; Antimicrobial Cationic Peptides - pharmacology; Base Sequence; Biological and medical sciences; Cloning, Molecular; DNA Primers; Fishes - genetics; Fundamental and applied biological sciences. Psychology; Fusarium - drug effects; Gene expression; Hepcidins; Marine; Marine Biology; Microbial Sensitivity Tests; Molecular Sequence Data; PC-hepc; Polymerase Chain Reaction; Pseudosciaena crocea; Recombinant Proteins - genetics; Recombinant Proteins - pharmacology; RNA, Messenger - genetics; Sequence Homology, Amino Acid; Staphylococcus aureus - drug effects; Synthetic peptide; Vertebrates: endocrinology; Vibrio alginolyticus; PC-hepc; Antimicrobial activity; Synthetic peptide; Pseudosciaena crocea; Gene expression; Gene; Peptides; Antibacterial agent; Antimicrobial agent
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/j.peptides.2008.12.014

Hepcidin gene is widely expressed in various fish, suggesting that this antimicrobial peptide is a very important component in the innate immune system. Large yellow croaker ( Pseudosciaena crocea) is one of the important economic species of marine-cultured fish but knowledge of its innate immune mechanism is lacking. In this study, we characterize a P. crocea hepcidin gene named as PC-hepc. It consists of an open reading frame of 258 bases encoding 85 amino acids and has a conserved sequence in common with other known hepcidins. The genomic DNA of PC-hepc contains three exons and two introns, the same organization as other reported hepcidins, indicating that PC-hepc is one member of the hepcidin family in fish. The tissue-specific expression of PC-hepc gene in normal fish and the expression pattern in LPS-challenged fish at the time course of stimulation were investigated. The expression of PC-hepc mRNA was significantly increased in the spleen, heart and stomach but not significantly induced in the liver after LPS challenge. An interesting finding is the demonstration of high amounts of PC-hepc transcripts in the kidney in normal fish and their maintenance through 48 h exposure to LPS challenge. The synthetic PC-hepc demonstrated a rather wide spectrum of antimicrobial activity in vitro against bacteria and fungi tested, and particularly showed strong activity against the principal fish pathogens, Aeromonas hydrophila, Vibrio parahaemloyticus, Vibrio alginolyticus and Vibrio harvryi. The study indicates that PC-hepc may play a role with a tissue-specific mode in the innate immunity of P. crocea.