Molecular identification and expression analysis of natural resistance associated macrophage protein (Nramp) cDNA from Japanese flounder (Paralichthys olivaceus).
Natural resistance associated macrophage protein (Nramp) controls partially innate resistance to intracellular parasites. Its function is to enhance the ability of macrophages to kill pathogens. However, little is known about the structure and function of Nramp in lower vertebrates such as teleosts. We have recently isolated a cDNA encoding Nramp from Japanese flounder (Paralichthys olivaceus). The full-length cDNA of the Nramp is 3066 bp in length, including 224 bp 5' terminal UTR, 1662 bp encoding region and 1180 bp 3' terminal UTR. The 1662-nt open reading frame was found to code for a protein with 554 amino acid residues. Comparison of amino acid sequence indicated that Japanese flounder Nramp consists of 12 transmembrane (TM) domains. A consensus transport motif (CTM) containing 20 residues was observed between transmembrane domains 8 and 9. The deduced amino acid sequence of Japanese flounder had 77.30%, 82.71%, 82.67%, 79.64%, 80.72%, 90.97%, 91.16%, 60.14%, 71.48%, 61.69%, 72.37% identity with that of rainbow trout Nramp alpha and beta, channel catfish Nramp, fathead minnow Nramp, common carp Nramp, striped sea bass Nramp, red sea bream Nramp, mouse Nramp 1 and 2, human Nramp 1 and 2, respectively. RT-PCR indicated that Nramp transcripts were highly abundant in spleen, head kidney, abundant in intestine, liver and gill, and less abundant in heart. The level of Nramp mRNA in embryos gradually increases during embryogenesis from 4 h (8 cell stage) to 80 h (hatched stage) after fertilization.
Yellow Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, Key Lab For Sustainable Utilization of Marine Fisheries Resources, Ministry of Agriculture, Qingdao 266071, China. chensl@ysfri.ac.cn
Song-Lin
SL
Chen
Zhi-Jian
ZJ
Wang
Mei-Yu
MY
Xu
Jian-Fang
JF
Gui
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism*; D016000:Cluster Analysis; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D005432:Flounder / Q000235:genetics* / Q000378:metabolism; D040461:Gene Components; D015870:Gene Expression; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D000099173:Natural Resistance-associated Macrophage Protein 1
D027682:Cation Transport Proteins; D017931:DNA Primers; D018076:DNA, Complementary; D000099173:Natural Resistance-associated Macrophage Protein 1