title: Molecular cloning and antiviral activity of IFN-β promoter stimulator-1 (IPS-1) gene in Japanese flounder, Paralichthys olivaceus.
abstract: The mitochondrial adaptor, IFN-β promoter stimulator-1 (IPS-1), also known as MAVS/VISA/Cardif, plays a key role in the signal transduction of the RIG-1/MDA5 pathway to induce the production of interferons (IFNs) and other cytokines. In the present study, Japanese flounder (Paralichthys olivaceus) IPS-1 cDNA was cloned from Japanese flounder spleen using PCR-based methods. The full-length cDNA has 2235 nucleotides and encodes a polypeptide of 641 amino acids. The putative Japanese flounder IPS-1 protein contains an N-terminal CARD-like domain, a central proline-rich domain, a C-terminal transmembrane domain, and exhibits similarity to other teleost counterparts ranging from 20% to 34%. Semi-quantitative RT-PCR showed that Japanese flounder IPS-1 mRNA was expressed in all tissues examined. The expression level of flounder IPS-1 gene was unchanged in viral hemorrhagic septicemia virus (VHSV)-infected kidney as measured by quantitative real-time PCR (Q-PCR). In addition, Japanese flounder IPS-1-overexpressing cells were protected against hirame rhabdovirus (HIRRV) and VHSV infection as manifested by the delayed appearance of cytopathic effect (CPE) and decreased viral titers. Expression of IFN-inducible genes including Mx, ISG15 and IRF3 were also induced in the IPS-1-overexpressing cells. These results suggest that Japanese flounder IPS-1 is involved in the antiviral immunity as a one of the adaptors in fish IFN-activation pathway.
authors.affiliation: Aquatic Biotechnology Center of WCU Project, College of Veterinary Medicine, Gyeongsang National University, Jinju, Gyeongnam, South Korea.
authors.forename: Rhoda Mae C
authors.initials: RM
authors.lastname: Simora
authors.forename: Maki
authors.initials: M
authors.lastname: Ohtani
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Hikima
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Kondo
authors.forename: Ikuo
authors.initials: I
authors.lastname: Hirono
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Jung
authors.forename: Takashi
authors.initials: T
authors.lastname: Aoki
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D003588:Cytopathogenic Effect, Viral / Q000276:immunology; D005393:Fish Diseases / Q000276:immunology / Q000821:virology*; D005432:Flounder / Q000235:genetics* / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008969:Molecular Sequence Data; D029141:Novirhabdovirus / Q000276:immunology*; D010802:Phylogeny; D011070:Poly I-C / Q000276:immunology; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D018353:Rhabdoviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D016415:Sequence Alignment; D014162:Transfection / Q000662:veterinary
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D012313:RNA; D011070:Poly I-C