Molecular characterization and expression analysis of a hepcidin gene from rice field eel (Monopterus albus)
Hepcidin is a cysteine-rich, dual-function peptide with antimicrobial activity that plays crucial roles in iron homeostasis. A few hepcidin-like genes have been isolated from teleost. Here, we have identified a hepcidin-like gene from rice field eel (RFE), Monopterus albus. Nucleotide sequences including cDNA and genomic DNA (GenBank accession numbers: FJ436808 and FJ594996, respectively) and deduced amino acid sequences were presented. In the 949 bp-long genomic sequence, two introns and three exons were identified. The full-length cDNA encodes a prepropeptide of 90 amino acid residues. RTPCR analysis suggested that hepcidin transcripts are highly abundant in the liver and kidney, less abundant in the heart, skin, brain, blood cells, intestine, spleen and stomach and undetectable in muscle. After challenged with Aeromonas hydrophila infection or iron-dextran stimulation, the hepcidin transcript levels were analyzed by RT-PCR. The results revealed that the expression of hepcidin dramatically increased at 24 h post-infection of the pathogen injection. Moreover, hepcidin mRNAs in the liver, intestine and brain were 2.4, 1.5 and 2-fold increase, respectively, compared with the control animals after 5 days in iron-dextran injected RFEs.
Key words: Rice field eel, Monopterus albus, hepcidin, gene expression