Cloning of an orange-spotted grouper (Epinephelus coioides) Mx cDNA and characterisation of its expression in response to nodavirus.
Molecular cloning and nucleotide sequencing of cDNA encoding an orange-spotted grouper (Epinephelus coioides) homolog of Mx ("OsgMx") was conducted and its possible role in fish immunity was analysed. Similar to mammalian Mx, the OsgMx are members of a family of interferon-inducible genes that are expressed by cells in response to nodavirus and iridovirus naturally-infected. Expression of OsgMx mRNA was noticeably upregulated in all tissues by nodavirus naturally-infected grouper. The transcription of OsgMx gene increased 6 h after intramuscular injection of nodavirus experimentally-infected fish and peaked at 72 h in their brains. Analysis of the 5'-flanking sequence of the gene shows that as in pufferfish and zebrafish, the OsgMx promoter contains two potential interferon-stimulated response element (ISRE) responsible for the induction of interferon-inducer polyinosinic-polycytidylic acid (Poly[I:C]). Transient transfection of grouper cells in gfp-reporter gene assays shows that the activation of the grouper Mx promoter fragment by Poly[I:C] is sufficient to allow the expression of green fluorescent protein (GFP). These results may provide a possible regulated pathway against nodavirus.
Chen
Young-Mao
YM
Institute of Biotechnology, College of Science, National Cheng Kung University, Tainan, 701, Taiwan.
Su
Yong-Lin
YL
Lin
John Han-You
JH
Yang
Huey-Lang
HL
Chen
Tzong-Yueh
TY
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D016000:Cluster Analysis; D017931:DNA Primers; D005393:Fish Diseases / Q000378:metabolism* / Q000821:virology*; D019204:GTP-Binding Proteins / Q000235:genetics*; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins; D008969:Molecular Sequence Data; D064547:Myxovirus Resistance Proteins; D030381:Nodaviridae; D010473:Perciformes / Q000235:genetics*; D010802:Phylogeny; D011070:Poly I-C / Q000378:metabolism; D012327:RNA Virus Infections / Q000378:metabolism / Q000662:veterinary*; D020218:Response Elements / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D014162:Transfection / Q000662:veterinary
D017931:DNA Primers; D064547:Myxovirus Resistance Proteins; D049452:Green Fluorescent Proteins; D019204:GTP-Binding Proteins; D011070:Poly I-C