title: Chemical genetics approach to hepatitis C virus replication: cyclophilin as a target for anti-hepatitis C virus strategy.
abstract: Hepatitis C virus (HCV) is a major causative agent of liver diseases such as chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Because the current standard therapy, interferon (IFN) or pegylated-IFN alone or in combination with ribavirin, is ineffective on approximately half of the HCV-infected patients, alternative therapeutics are greatly needed. The chemical genetics method is a useful strategy to elucidate molecular mechanisms of the viral life cycle and screen for anti-viral agents. This review focuses on the use of chemical genetics approach to virology, which could be called 'chemical virology', and introduces an example of such analysis. From a cell culture-based screening, an immunosuppressant cyclosporin A (CsA) was identified as an anti-HCV compound. Analysis using CsA as a bioprobe showed that cyclophilin (CyP) B, a cellular target of CsA, regulates the function of HCV RNA polymerase NS5B, which is essential for efficient viral genome replication. By targeting CyP, HCV genome replication was drastically suppressed. Thus, chemical genetics analysis identified CyPB as a cellular cofactor of HCV genome replication and a target for novel anti-HCV agents.
authors.affiliation: Department of Viral Oncology, Institute for Virus Research, Kyoto University, Kyoto, Japan. kwatashi@virus.kyoto-u.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Watashi
authors.forename: Kunitada
authors.initials: K
authors.lastname: Shimotohno
mesh_terms: D000998:Antiviral Agents / Q000378:metabolism / Q000494:pharmacology*; D021983:Cyclophilins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016572:Cyclosporine / Q000009:adverse effects / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006526:Hepatitis C / Q000188:drug therapy / Q000821:virology; D006801:Humans; D007166:Immunosuppressive Agents; D019696:Peptidylprolyl Isomerase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D007166:Immunosuppressive Agents; C081786:cyclophilin B; D016572:Cyclosporine; C090438:(melle-4)cyclosporin; D021983:Cyclophilins; D019696:Peptidylprolyl Isomerase