title: Arginine 112 is involved in HCV translation modulation by NS5A domain I.
abstract: HCV NS5A has three domains, which have multiple roles in the viral life cycle. We previously found that NS5A is able to down-regulate HCV RNA translation through a mechanism requiring the polyU/UC region within the viral 3'UTR to which NS5A binds. In this study, we further investigated the role of domain I in modulating viral translation. Using a series of deletion and substitution mutants, we identified a number of positively charged residues that played a role in this modulatory effect, most prominently R112. The R112A mutation negated the ability of domain I and full-length NS5A to modulate viral translation. Additionally, the R112A mutation impeded domain I binding to the polyU/UC RNA, suggesting a mechanism for this down-regulatory effect. Finally, the R112A mutation rendered HCV replication deficient. These results collectively point to a crucial role for the R112 residue of NS5A in the modulation of HCV life cycle by NS5A.
authors.affiliation: VIDO-InterVac and Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors.forename: Brett
authors.initials: B
authors.lastname: Hoffman
authors.affiliation: VIDO-InterVac, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors.forename: Qing
authors.initials: Q
authors.lastname: Shi
authors.affiliation: VIDO-InterVac, Veterinary Microbiology, Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. Electronic address: qiang.liu@usask.ca.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
mesh_terms: D020413:3' Untranslated Regions; D001120:Arginine / Q000737:chemistry* / Q000378:metabolism; D045744:Cell Line, Tumor; D015967:Gene Expression Regulation, Viral; D017930:Genes, Reporter; D016174:Hepacivirus / Q000235:genetics* / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism / Q000821:virology; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D014176:Protein Biosynthesis; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D017361:Viral Nonstructural Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase
chemical_list: D020413:3' Untranslated Regions; D001120:Arginine; D008156:Luciferases; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase
keywords: 3′UTR; HCV NS5A domain I; HCV RNA translation; HCV replication; RNA binding