title: Molecular characterization and IFN signal pathway analysis of Carassius auratus CaSTAT1 identified from the cultured cells in response to virus infection.
abstract: Type I interferon (IFN) exerts its pleiotropic effects mainly through the JAK-STAT signaling pathway, which is presently best described in mammals. By subtractive suppression hybridization, two fish signaling factors, JAK1 and STAT1, had been identified in the IFN-induced crucian carp Carassius auratus L. blastulae embryonic (CAB) cells after treatment with UV-inactivated grass carp hemorrhagic virus (GCHV). Further, the full-length cDNA of STAT1, termed CaSTAT1, was obtained. It contains 2926 bp and encodes a protein of 718 aa. CaSTAT1 is most similar to rat STAT1 with 59% identity overall and displays all highly conserved domains that the STAT family possesses. Like human STAT1beta, it lacks the C-terminus acting as transcriptional activation domain in mammals. By contrast, only a single transcript was detected in virus-induced CAB cells. Expression analysis showed that CaSTAT1 could be activated by stimulation of CAB cells with poly I:C, active GCHV, UV-inactivated GCHV or CAB IFN, and displayed diverse expression patterns similar to that of mammalian STAT1. Additionally, the expression of an antiviral gene CaMx1 was also induced under the same conditions, and expression difference between CaSTAT1 and CaMx1 was revealed by induction of CAB IFN. These results provide molecular evidence supporting the notion that the fish IFN signaling transduction pathway is similar to that in mammals. Fish IFN exerts its multiple functions, at least antiviral action, through a JAK-STAT pathway.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Department of Fish Genetics and Breeding, Institute of Hydrobiology, Wuhan Center for Developmental Biology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China.
authors.forename: Yibing
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jianfang
authors.initials: J
authors.lastname: Gui
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D036703:Blastula / Q000166:cytology / Q000821:virology; D015152:Blotting, Northern; D002460:Cell Line; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D029941:Fish Proteins / Q000235:genetics / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects; D018507:Gene Expression Regulation, Developmental; D006054:Goldfish / Q000235:genetics / Q000502:physiology* / Q000821:virology; D007370:Interferon Type I / Q000494:pharmacology / Q000502:physiology*; D007700:Kinetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D011070:Poly I-C / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D012087:Reoviridae / Q000528:radiation effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology*; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology; D014466:Ultraviolet Rays; D038301:Virus Inactivation
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D007370:Interferon Type I; D012333:RNA, Messenger; D015534:Trans-Activators; D011070:Poly I-C