title: Bovine viral diarrhea virus non-structural protein 5A interacts with NIK- and IKKbeta-binding protein.
abstract: Bovine viral diarrhea virus (BVDV) is a positive-sense, single-stranded RNA virus that causes an economically important livestock disease worldwide. Previous studies have suggested that non-structural protein 5A (NS5A) from hepatitis C virus (HCV) and BVDV plays a similar role during virus infection. Extensive reports are available on HCV NS5A and its interactions with the host cellular proteins; however, the role of NS5A during BVDV infection remains largely unclear. To identify the cellular proteins that interact with the N terminus of NS5A and could be involved in its function, we conducted a yeast two-hybrid screening. As a result, we identified a cellular protein termed bovine NIK- and IKKbeta-binding protein (NIBP), which is involved in protein trafficking and nuclear factor kappa B (NF-kappaB) signalling in cells. The interaction of NS5A with NIBP was confirmed both in vitro and in vivo. Complementing our glutathione S-transferase pull-down and immunoprecipitation data are the confocal immunofluorescence results, which indicate that NS5A colocalized with NIBP on the endoplasmic reticulum in the cytoplasm of BVDV-infected cells. Moreover, the minimal residues of NIBP that interact with NS5A were mapped as aa 597-623. In addition, overexpression of NS5A inhibited NF-kappaB activation in HEK293 and LB9.K cells as determined by luciferase reporter-gene assay. We further showed that inhibition of endogenous NIBP by small interfering RNA molecules enhanced virus replication, indicating the importance of NIBP implications in BVDV pathogenesis. Being the first reported interaction between NIBP and a viral protein, this finding suggests a novel mechanism whereby viruses may subvert host-cell machinery for mediating trafficking as well as NF-kappaB signalling.
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Muhammad Atif
authors.initials: MA
authors.lastname: Zahoor
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamane
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yassir Mahgoub
authors.initials: YM
authors.lastname: Mohamed
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Suda
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Kyousuke
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kato
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yukinobu
authors.initials: Y
authors.lastname: Tohya
authors.affiliation: Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Hiroomi
authors.initials: H
authors.lastname: Akashi
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002417:Cattle; D002460:Cell Line; D030241:Diarrhea Virus 1, Bovine Viral / Q000502:physiology*; D004721:Endoplasmic Reticulum / Q000737:chemistry; D020868:Gene Silencing; D017930:Genes, Reporter; D054884:Host-Pathogen Interactions; D006801:Humans; D047468:Immunoprecipitation; D008156:Luciferases; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D011485:Protein Binding; D025941:Protein Interaction Mapping; D034741:RNA, Small Interfering; D020798:Two-Hybrid System Techniques; D017361:Viral Nonstructural Proteins / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D016328:NF-kappa B; D034741:RNA, Small Interfering; D017361:Viral Nonstructural Proteins; D008156:Luciferases