Okamoto Lab/Division of Infectious Disease  Institute for Advanced Co-Creation Studies

Our research is focusing on the pathogenesis of with hepatitis viruses, such as Hepatitis C virus and Hepatitis B virus and mosquito-borne flaviviruse such as Japanese encephalitis virus (JEV), Dengue virus (DENV) and Zika virus (ZIKV). It still remains unclear how these viruses induce a variety of diseases in hosts. We aim to study to understand molecular mechanisms of pathogenicity of virus infections through molecular biology and animal models.

Pathogenicity of hepatitis viruses

Infection with Hepatitis C virus (HCV) induces chronic infection and leads to develop steatosis, cirrhosis and hepatocellular carcinoma. Among 10 viral proteins, HCV core protein forms a viral particle and induces steatosis and hepatocellular carcinoma in transgenic mice model. It suggests that core is strongly associated with liver diseases in chronic hepatitis C. Our research is focusing on maturation of core protein by signal peptide peptidase (SPP) and its maturation is essential for formation of viral particle and development of liver diseases. We would like to clarify why maturation of HCV core is needed for its function, especially liver diseases.

 

Pathology of mosquito-borne flavivirus and development of new antiviral drugs

Infectious diseases by infection with mosquito-borne flavivirus, one of which is microcephaly by infection with Zika virus, have become a serious problem worldwide . Mosquito-borne flavivirus spreads infection through blood feeding of virus-infected mosquito. While host ranges of virus infection are generally limited, mosquito-borne flavivirus can propagate mosquito and mammals. We study how mosquito-borne flavivirus infects mosquito and mammals and how transmission between mosquito and mammals is associate to development of diseases

 

 

 

Staff

  • Prof.: Toru Okamoto
  • Assit. Prof.: Tatsuya Suzuki
  • Postdoc.: Yumi Ito

Website

Publications

  • (1) Novel anti-flavivirus drugs targeting the nucleolar distribution of core protein. Tokunaga M., et al. Virology 2019 541:41-51
    (2) Infection with flaviviruses requires BCLXL for cell survival. Suzuki T. & Okamoto T., et al., PLoS Pathog. 2018 Sep 27; 14 (9):e1007299.
    (3)Characterization of SPP inhibitors suppressing propagation of HCV and protozoa. Hirano J. & Okamoto T., et al., Proc Natl Acad Sci U S A. 2017 Dec 12;114 (50):E10782-E10791.
    (4) TRC8-dependent degradation of hepatitis C virus immature core protein regulates viral propagation and pathogenesis. Aizawa S. & Okamoto T., et al., Nat. Commun. 2016 May 6; 12(5): e1005610