title: Complex formation of NS5B with NS3 and NS4A proteins of hepatitis C virus.
abstract: At present, the mechanism of replication of the HCV genome remains unclear. Recently, NS5B and NS3 of HCV have been shown to exhibit RNA-dependent RNA polymerase and helicase activities, respectively, both of which are indispensable for virus RNA replication. In this study, we examined the complex formation of NS5B with NS3 and NS4A, a cofactor for NS3. We show here that NS5B forms a complex with NS3 through an amino-terminal portion of NS3. The NS3-NS5B complex formation took place both in the presence and absence of NS4A. We also demonstrate that NS5B form a complex with NS4A in the absence of NS3. These results suggest that NS3, NS4A and NS5B interact with each other to form a complex that functions as part of the replication machinery of HCV.
authors.affiliation: Department of Microbiology, Kobe University School of Medicine, Hyogo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ishido
authors.forename: T
authors.initials: T
authors.lastname: Fujita
authors.forename: H
authors.initials: H
authors.lastname: Hotta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002467:Cell Nucleus / Q000201:enzymology / Q000821:virology; D003593:Cytoplasm / Q000201:enzymology / Q000821:virology; D006367:HeLa Cells; D016174:Hepacivirus / Q000201:enzymology*; D006801:Humans; D009097:Multienzyme Complexes / Q000378:metabolism*; D012316:RNA Nucleotidyltransferases / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism; D013347:Subcellular Fractions / Q000201:enzymology / Q000821:virology; D017361:Viral Nonstructural Proteins / Q000378:metabolism*; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D009097:Multienzyme Complexes; D012316:RNA Nucleotidyltransferases; D012324:RNA-Dependent RNA Polymerase; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C093542:NS4 protein, hepatitis C virus; C087036:NS-5 protein, hepatitis C virus