title: Similar roles for yeast Dbp2 and Arabidopsis RH20 DEAD-box RNA helicases to Ded1 helicase in tombusvirus plus-strand synthesis.
abstract: Recruited host factors aid replication of plus-strand RNA viruses. In this paper, we show that Dbp2 DEAD-box helicase of yeast, which is a homolog of human p68 DEAD-box helicase, directly affects replication of Tomato bushy stunt virus (TBSV). We demonstrate that Dbp2 binds to the 3'-end of the viral minus-stranded RNA and enhances plus-strand synthesis by the viral replicase in a yeast-based cell-free TBSV replication assay. In vitro data with wt and an ATPase-deficient Dbp2 mutant indicate that Dbp2 unwinds local secondary structures at the 3'-end of the TBSV (-)RNA. We also show that Dbp2 complements the replication deficiency of TBSV in yeast containing reduced amount of Ded1 DEAD-box helicase, another host factor involved in TBSV replication, suggesting that Dbp2 and Ded1 helicases play redundant roles in TBSV replication. We also show that the orthologous AtRH20 DEAD-box helicase from Arabidopsis can increase tombusvirus replication in vitro and in yeast.
authors: Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, United States.
authors: Nikolay
authors: N
authors: Kovalev
authors: Daniel
authors: D
authors: Barajas
authors: Peter D
authors: PD
authors: Nagy
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D053487:DEAD-box RNA Helicases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D012367:RNA, Viral / Q000096:biosynthesis*; D012324:RNA-Dependent RNA Polymerase; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D017864:Tombusvirus / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D014779:Virus Replication
chemical_list: D012367:RNA, Viral; D029701:Saccharomyces cerevisiae Proteins; D012324:RNA-Dependent RNA Polymerase; C492152:DED1 protein, S cerevisiae; C438898:Dbp2 protein, S cerevisiae; D053487:DEAD-box RNA Helicases