title: Molecular cloning, characterization and expression analysis of interferon-β promoter stimulator 1 (IPS-1) gene from grass carp Ctenopharyngodon idella.
abstract: IPS-1 (interferon-β promoter stimulator 1), also known as MAVS/VISA/Cardif, plays a central role in antiviral immunity. In this manuscript, we cloned and characterized IPS-1 from grass carp Ctenopharyngodon idella (designated as CiIPS-1). The CiIPS-1 cDNA is 2412 bp long and consists of a 5' untranslated region (UTR) of 124 bp, a 3' UTR of 497 bp with three cytokine RNA instability motifs (ATTTA) and a polyadenylation signal (AATAAA), and an open reading frame (ORF) of 1791 bp encoding a polypeptide of 596 amino acids with a calculated molecular mass of 64.1 kDa and a theoretical isoelectric point of 4.79. Structural analysis showed that the CiIPS-1 protein contained an N-terminal CARD (caspase activation and recruitment domain), a central proline-rich domain, a putative TRAF2-binding motif and a C-terminal transmembrane domain. Similarity analysis of the deduced amino acid sequence of the CiIPS-1 by MatGAT software revealed that the CiIPS-1 shared 27.8-76.4% identity and 47.4-85.2% similarity with other known piscine IPS-1 sequences. The CiIPS-1 mRNA was constitutively expressed in the examined tissues, higher in spleen, and was induced by grass carp reovirus (GCRV) injection by semi-quantitative RT-PCR assay. Quantitative real-time RT-PCR analysis revealed that the CiIPS-1 mRNA expression was rapidly and significantly up-regulated in vivo and in vitro after GCRV infection, and the CiIPS-1 transcripts were also significantly enhanced in vitro post the synthetic double stranded RNA polyinosinic-polycytidylic potassium salt (poly(I:C)) stimulation. These results indicated that CiIPS-1 was an inducible acute-phase protein and involved in the immune reaction to GCRV in grass carp.
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China. su.jianguo@gmail.com
authors.forename: Jianguo
authors.initials: J
authors.lastname: Su
authors.forename: Teng
authors.initials: T
authors.lastname: Huang
authors.forename: Chunrong
authors.initials: C
authors.lastname: Yang
authors.forename: Rongfang
authors.initials: R
authors.lastname: Zhang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002347:Carps; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation / Q000502:physiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012087:Reoviridae; D012088:Reoviridae Infections / Q000378:metabolism / Q000662:veterinary / Q000821:virology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D018076:DNA, Complementary; D012333:RNA, Messenger