title: Cell-line-induced mutation of the rotavirus genome alters expression of an IRF3-interacting protein.
abstract: Rotavirus, a cause of severe gastroenteritis, contains a segmented double-stranded (ds)RNA genome that replicates using viral mRNAs as templates. The highly conserved 3'-consensus sequence (3'CS), UGUGACC, of the mRNAs promotes dsRNA synthesis and enhances translation. We have found that the 3'CS of the gene (g5) encoding NSP1, an antagonist of interferon signaling, undergoes rapid mutation when rhesus rotavirus (RRV) is serially passaged at high multiplicity of infection (MOI) in cells permitting high titer growth. These mutations increase the promoter activity of the g5 3'-sequence, but decrease its activity as a translation enhancer. The location of the mutations defines the minimal essential promoter for dsRNA synthesis as URN0-5CC. Under passage conditions where cell-to-cell spread of the virus is required to complete infection (low MOI), the 3'CS is retained due to the need for NSP1 to be expressed at levels sufficient to prevent establishment of the antiviral state. These data demonstrate that host cell type and propagation conditions affect the capacity of RRV to produce the virulence gene product NSP1, an important consideration in producing RRV-based vaccines.
authors.affiliation: Laboratory of Infectious Diseases, National Institutes of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Kearney
authors.forename: Dayue
authors.initials: D
authors.lastname: Chen
authors.forename: Zenobia F
authors.initials: ZF
authors.lastname: Taraporewala
authors.forename: Patrice
authors.initials: P
authors.lastname: Vende
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Hoshino
authors.forename: Maria Alejandra
authors.initials: MA
authors.lastname: Tortorici
authors.forename: Mario
authors.initials: M
authors.lastname: Barro
authors.forename: John T
authors.initials: JT
authors.lastname: Patton
mesh_terms: D000818:Animals; D002460:Cell Line; D016384:Consensus Sequence / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D004926:Escherichia coli / Q000235:genetics; D015967:Gene Expression Regulation, Viral; D014644:Genetic Variation; D016679:Genome, Viral; D008954:Models, Biological; D009154:Mutation; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012330:RNA, Double-Stranded / Q000235:genetics / Q000378:metabolism; D012401:Rotavirus / Q000235:genetics* / Q000502:physiology; D012692:Serial Passage; D017361:Viral Nonstructural Proteins / Q000235:genetics* / Q000378:metabolism*; D010948:Viral Plaque Assay; D014779:Virus Replication
chemical_list: D012330:RNA, Double-Stranded; D017361:Viral Nonstructural Proteins; C104282:nsp1 protein, Rotavirus