Identification of DreI as an antiviral factor regulated by RLR signaling pathway

• Published in: PloS one 2012-03, Vol.7 (3), p.e32427
• Main Authors: Li, Shun, Sun, Fan, Zhang, Yi-Bing, Gui, Jian-Fang, Zhang, Qi-Ya
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animal genetic engineering; Animals; Antiviral activity; Antiviral Agents - metabolism; Antiviral Agents - pharmacology; Antiviral drugs; Antiviral state; Base Sequence; Biological response modifiers; Biology; Carassius carassius; Carp; Carps; Cytoplasm - metabolism; Danio rerio; Data processing; Fish; Fishes; Gene Expression - drug effects; Grass carp reovirus; Health aspects; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Homeodomain Proteins - pharmacology; Homology; Infection; Infections; Interferon; Interferon regulatory factor 3; Kinases; Molecular Sequence Data; Mutation; Nucleotide Motifs; Oncorhynchus mykiss; Poly (I:C); Poly I-C - pharmacology; Polyinosinic:polycytidylic acid; Polymerase chain reaction; Promoter Regions, Genetic; Promoters; Protein Transport; Rana grylio; Receptors; Regulatory sequences; Retinoic acid; RNA Helicases - metabolism; Sequence Alignment; Signal Transduction; Signaling; Spring viremia of carp virus; Transcription Factor Brn-3C - genetics; Transcription Factor Brn-3C - metabolism; Transcription Factor Brn-3C - pharmacology; Viral infections; Viremia; Viruses; Western blotting; Zebrafish; Zebrafish - genetics; Zebrafish - metabolism; Zebrafish Proteins - genetics; Zebrafish Proteins - metabolism; Zebrafish Proteins - pharmacology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0032427

Retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) had been demonstrated to prime interferon (IFN) response against viral infection via the conserved RLR signaling in fish, and a novel fish-specific gene, the grass carp reovirus (GCRV)-induced gene 2 (Gig2), had been suggested to play important role in host antiviral response. In this study, we cloned and characterized zebrafish Gig2 homolog (named Danio rerio Gig2-I, DreI), and revealed its antiviral role and expressional regulation signaling pathway. RT-PCR, Western blot and promoter activity assay indicate that DreI can be induced by poly I:C, spring viremia of carp virus (SVCV) and recombinant IFN (rIFN), showing that DreI is a typical ISG. Using the pivotal signaling molecules of RLR pathway, including RIG-I, MDA5 and IRF3 from crucian carp, it is found that DreI expression is regulated by RLR cascade and IRF3 plays an important role in this regulation. Furthermore, promoter mutation assay confirms that the IFN-stimulated regulatory elements (ISRE) in the 5' flanking region of DreI is essential for its induction. Finally, overexpression of DreI leads to establish a strong antiviral state against SVCV and Rana grylio virus (RGV) infection in EPC (Epithelioma papulosum cyprinid) cells. These data indicate that DreI is an antiviral protein, which is regulated by RLR signaling pathway.