Natural Resistance Associated Macrophage Protein Is Involved in Immune Response of Blunt Snout Bream, Megalobrama amblycephala.

The natural resistance-associated macrophage protein gene (), has been identified as one of the significant candidate genes responsible for modulating vertebrate natural resistance to intracellular pathogens. Here, we identified and characterized a new family member, named as , in the blunt snout bream. The full-length cDNA of consists of a 153 bp 5'UTR, a 1635 bp open reading frame encoding a protein with 544 amino acids, and a 1359 bp 3'UTR. The deduced protein (maNRAMP) possesses the typical structural features of NRAMP protein family, including 12 transmembrane domains, three N-linked glycosylation sites, and a conserved transport motif. Phylogenetic analysis revealed that maNRAMP shares the significant sequence consistency with other teleosts, and shows the higher sequence similarity to mammalian than . It was found that expressed ubiquitously in all normal tissues tested, with the highest abundance in the spleen, followed by the head kidney and intestine, and less abundance in the muscle, gill, and kidney. After lipopolysaccharide (LPS) stimulation, the mRNA level of was rapidly up-regulated, which reached a peak level at 6 h. Altogether, these results indicated that might be related to fish innate immunity and similar to mammalian in function.