title: Single-point mutations of hepatitis C virus NS3 that impair p53 interaction and anti-apoptotic activity of NS3.
abstract: The N-terminal domain of NS3 of hepatitis C virus (HCV) possesses serine protease activity, which is essential for virus replication. This portion is also implicated in malignant transformation of hepatocytes. We previously demonstrated that an N-terminal portion of NS3 formed a complex with the tumor suppressor p53 and suppressed actinomycin D-induced apoptosis. We report here that single-point mutations of NS3 at position 106 from Leu to Ala (L106A), and position 43 from Phe to Ala (F43A) to a lesser extent, significantly impaired complex formation with p53. Moreover, the L106A mutation impaired an otherwise more distinct anti-apoptotic activity of NS3. F43A and L106A mutations also inhibited serine protease activity of NS3. These results collectively suggest the possibility that Leu106 and Phe43 are involved in p53 interaction and serine protease activity, and therefore, can be a good target for certain low-molecular-weight compound(s) to inhibit both oncogenic and replicative abilities of HCV.
authors.affiliation: Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.
authors.forename: Motofumi
authors.initials: M
authors.lastname: Tanaka
authors.forename: Motoko
authors.initials: M
authors.lastname: Nagano-Fujii
authors.forename: Lin
authors.initials: L
authors.lastname: Deng
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ishido
authors.forename: Kiyonao
authors.initials: K
authors.lastname: Sada
authors.forename: Hak
authors.initials: H
authors.lastname: Hotta
mesh_terms: D000409:Alanine / Q000737:chemistry; D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D017931:DNA Primers / Q000737:chemistry; D016158:Genes, p53; D006367:HeLa Cells; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D007930:Leucine / Q000737:chemistry; D051379:Mice; D008856:Microscopy, Fluorescence; D008957:Models, Genetic; D009154:Mutation; D041681:NIH 3T3 Cells; D010649:Phenylalanine / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012697:Serine Endopeptidases / Q000737:chemistry; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D017361:Viral Nonstructural Proteins / Q000737:chemistry*; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D000409:Alanine; D017931:DNA Primers; D007930:Leucine; D010649:Phenylalanine; D012697:Serine Endopeptidases; D016159:Tumor Suppressor Protein p53; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C495901:TP53 protein, human