title: Identification of two novel interferon-stimulated genes from cultured CAB cells induced by UV-inactivated grass carp hemorrhage virus.
abstract: Interferon (IFN) exerts its antiviral effect by inducing the expression of a number of IFN-stimulated genes (ISGs) to establish a host antiviral state. Earlier studies identified some important fish IFN system genes from IFN-induced CAB cells (crucian carp Carassius auratus L. embryonic blastulae cells) after treatment with UV-inactivated GCHV (grass carp hemorrhage virus). Herein, the cloning of 2 novel IFN-stimulated genes, termed Gig1 and Gig2, is described for the same cell system. The complete cDNA sequences of Gig1 and Gig2 contain 1244 bp encoding for a 194-amino-acid protein and 693 bp for a 158-amino-acid protein, respectively. A search of public databases revealed that these are 2 novel IFN-stimulated genes, since neither significant homologous genes nor conserved motifs were identified. Active GCHV, UV-inactivated GCHV and CAB IFN-containing supernatant (ICS) induced transcription of these genes and distinct kinetics were observed. An analysis of differences in expression between the 2 genes and the IFN signal factors CaSTAT1 and CaIRF7 indicated that GCHV infection activated different signal pathways for their up-regulation. Upon virus infection, the transcription of Gig1 but not of Gig2 is strongly suppressed by cycloheximide (CHX). In contrast, following treatment with CAB IFN-containing supernatant, CHX does not inhibit either gene transcription. The results suggest that GCHV infection can induce expression of both Gig1 and Gig2 via newly synthesized CAB IFN, most probably through the JAK-STAT signal pathway, and can also directly activate Gig2 transcription without ongoing protein synthesis.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Wuhan Center for Developmental Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China.
authors.forename: Yi Bing
authors.initials: YB
authors.lastname: Zhang
authors.forename: Jian Fang
authors.initials: JF
authors.lastname: Gui
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002347:Carps / Q000235:genetics* / Q000821:virology; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D050839:Interferon Regulatory Factor-7; D007372:Interferons / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D012087:Reoviridae / Q000502:physiology / Q000528:radiation effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050794:STAT1 Transcription Factor; D017422:Sequence Analysis, DNA; D015398:Signal Transduction / Q000502:physiology*; D015534:Trans-Activators / Q000378:metabolism
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029941:Fish Proteins; D050839:Interferon Regulatory Factor-7; D050794:STAT1 Transcription Factor; D015534:Trans-Activators; D007372:Interferons; D003513:Cycloheximide