title: EcVig, a novel grouper immune-gene associated with antiviral activity against NNV infection.
abstract: VHSV-induced genes (VIGs) were first identified in rainbow trout (Oncorhynchus mykiss) and subsequently isolated in a variety of fish. Recent studies have shown that most VIGs have immunological functions against pathogenic infections. However, most research has focused on Vig1, such that our present understanding of these genes in other fish species remains limited. This study isolated a homologue of the uncharacterized O. mykiss Vig-B319 (EcVig) from orange-spotted grouper (Epinephelus coioides). Genomic organization suggests that four EcVig isoforms (EcVig A-D), are generated through alternative splicing. Due to the encoding of 2 immunoglobulin (Ig) domains, the EcVig protein can be considered a member of the immunoglobulin superfamily. The expression of EcVig increased 3 days after hatching (dph) and peaked at 9 dph. This pattern is similar to that displayed by EcMx, an important grouper antiviral gene. Additionally, a tissue tropism assay revealed that EcVig A is the major EcVig isoform present in the tissues considered by this study, with the expression of EcVig A exceeding that of EcVig B. We subsequently investigated whether EcVig expression was induced by the viral pathogen nervous necrosis virus (NNV) or the bacterial pathogen Vibrio anguillarum. Following injection with NNV, the expression levels of EcVig showed significant up-regulation. Conversely, a significant reduction was observed in EcVig expression in brain samples collected from V. anguillarum injected grouper. The overexpression of EcVig A suppressed the replication of NNV in grouper GF-1 cell lines, suggesting that EcVig is an important antiviral factor in the grouper immune responses.
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Yeh
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Yi-Jiou
authors.initials: YJ
authors.lastname: Hsu
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Yi-Min
authors.initials: YM
authors.lastname: Chen
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Han-You
authors.initials: HY
authors.lastname: Lin
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC; Merit Ocean Biotech Inc., Tainan, Taiwan, ROC.
authors.forename: Huey-Lang
authors.initials: HL
authors.lastname: Yang
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Tzong-Yueh
authors.initials: TY
authors.lastname: Chen
authors.affiliation: Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan, ROC. Electronic address: wanghc@mail.ncku.edu.tw.
authors.forename: Han-Ching
authors.initials: HC
authors.lastname: Wang
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D000998:Antiviral Agents / Q000378:metabolism*; D001921:Brain / Q000378:metabolism* / Q000821:virology; D002460:Cell Line; D005393:Fish Diseases / Q000276:immunology*; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D005399:Fishes / Q000276:immunology* / Q000821:virology; D005786:Gene Expression Regulation; D007109:Immunity; D007136:Immunoglobulins / Q000235:genetics / Q000378:metabolism*; D030381:Nodaviridae / Q000502:physiology*; D020033:Protein Isoforms / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics; D012327:RNA Virus Infections / Q000276:immunology*; D017386:Sequence Homology, Amino Acid; D019076:Transgenes / Q000235:genetics; D014733:Vibrio / Q000276:immunology*; D014735:Vibrio Infections / Q000276:immunology*; D014779:Virus Replication
chemical_list: D000998:Antiviral Agents; D029941:Fish Proteins; D007136:Immunoglobulins; D020033:Protein Isoforms; C446600:vig-2 protein, Oncorhynchus mykiss
keywords: Nervous necrosis virus (NNV); Orange-spotted grouper (Epinephelus coioides); VHSV induced gene (Vig)