title: Molecular cloning and characterization of crucian carp (Carassius auratus L.) interferon regulatory factor 7.
abstract: Interferon (IFN) can induce an antiviral state via interferon-regulatory transcription factors (IRFs), which bind to and control genes directed by the interferon-stimulated response element (ISRE). Here we describe a fish IRF, termed CaIRF7, cloned from a subtractive cDNA library which is constructed with mRNAs obtained from crucian carp (Carassius auratus L.) blastulae embryonic (CAB) cells infected by UV-inactivated GCHV and mock-infected cells. CaIRF7 cDNA was found to be 1816 bp in length, with a 42 bp 5'UTR and a 508 bp 3'UTR. The open reading frame translates into 421 amino acids in which a DNA-binding domain (DBD) containing the repeated tryptophan motif and IRFs association domain have been identified. Like chicken GgIRF3, CaIRF7 was most similar to mammalian IRF7 with 27 to 30% identity overall and some 37% identity in their DBDs. A single transcript of 1.9 kb was detected in virally induced CAB cells by virtual Northern blotting. RT-PCR analysis revealed a wide tissue distribution of CaIRF7 constitutive expression, with detectable transcript in non-infected CAB cells and various tissues of healthy crucian carp. In addition, CaIRF7 expression was differentially increased by stimulation of the CAB cells with active GCHV, UV-inactivated GCHV or CAB IFN, indicating that the activation of CaIRF7 was directly regulated by IFN.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Wuhan Center for Developmental Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Yi-bing
authors.initials: YB
authors.lastname: Zhang
authors.forename: Cheng-yu
authors.initials: CY
authors.lastname: Hu
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Guo-ping
authors.initials: GP
authors.lastname: Huang
authors.forename: Li-hua
authors.initials: LH
authors.lastname: Wei
authors.forename: Qi-ya
authors.initials: QY
authors.lastname: Zhang
authors.forename: Jian-fang
authors.initials: JF
authors.lastname: Gui
mesh_terms: D000818:Animals; D001483:Base Sequence; D036703:Blastula / Q000276:immunology; D015152:Blotting, Northern; D003001:Cloning, Molecular; D016000:Cluster Analysis; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000276:immunology*; D020869:Gene Expression Profiling; D006054:Goldfish / Q000235:genetics / Q000276:immunology*; D050839:Interferon Regulatory Factor-7; D008969:Molecular Sequence Data; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D050839:Interferon Regulatory Factor-7