Molecular cloning and characterization of transferrin from Hippocampus abdominalis  

Generally, transferrin is an iron transporting molecule. Moreover, it participates in host immunity as binding to iron (III) which important for bacterial survival. Typical transferrin has two similar iron (III) binding domains (transferrin N-lope and C-lope). As per current studies, it shows antibacterial activity either via Iron binding activity or by inducing NO (nitric oxide) production in macrophage. In this study, we identified a transferrin homolog from Hippocampus abdominalis. Seahorse cDNA transcriptome database was established using 454 GS FLX sequencing technique. In order to determine the immune responses of Shtransferrin, Streptococcus iniae (S. iniae), Edwardsiella tarda (E. tarda), LPS and the scutica were employed as immune stimulants in time course experiment.

In this study, Shtransferrin from Hippocampus abdominalis was identified and characterized. The cDNA of Shtransferrin composed of 2169 bp open reading frame that encoded 723 aa. Signal peptide was predicted at the N-terminus with 20 aa. Tissue-specific profiling showed ubiquitous expression in all tissues including blood, brain, gill, heart, intestine, liver, kidney, muscle, ovary, pouch, skin, spleen, stomach and testis. Shtransferrin was abundantly expressed in intestine followed by stomach (Fig.1). Significantly up-regulated pattern of Shtransferrin expression was observed at 12h, 48h and 72 h after induction by S. iniae and E. tarda in kidney tissues suggesting that shtransferrin is likely to play an important role in host immune defense against microbial infection.