Journal of Microbiology

, Volume 57, Issue 12, pp 1126–1131 | Cite as

Methyltransferase of a cell culture-adapted hepatitis E inhibits the MDA5 receptor signaling pathway

  • Jinjong MyoungEmail author
  • Jeong Yoon Lee
  • Kang Sang Min


Hepatitis E virus (HEV) is a causative agent of acute hepatitis and jaundice. The number of human infections is approximated to be over 20 million cases per year. The transmission is mainly via the fecal-oral route and contaminated water and food are considered to be a major source of infection. As a mouse model is not available, a recent development of a cell culture-adapted HEV strain (47832c) is considered as a very important tools for molecular analysis of HEV pathogenesis in cells. Previously, we demonstrated that HEV-encoded methyltransferase (MeT) encoded by the 47832c strain inhibits MDA5- and RIG-I-mediated activation of interferon β (IFN-β) promoter. Here, we report that MeT impairs the phosphorylation and activation of interferon regulatory factor 3 and the p65 subunit of NF-κB in a dose-dependent manner. In addition, the MeT encoded by the 47832c, but not that of HEV clinical or field isolates (SAR-55, Mex-14, KC-1, and ZJ-1), displays the inhibitory effect. A deeper understanding of MeTmediated suppression of IFN-β expression would provide basis of the cell culture adaptation of HEV.


hepatitis E virus methyltransferase interferon 


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This research was supported by Basic Science Research Program through the National Research Foundation (NRF) funded by the Ministry of Education (2017R1A6A1A03015876) and by a grant from the Center for Analytical Research of Disaster Science of Korea Basic Science Institute (C38711) to J. Kwon. J. Myoung was supported by “Research Base Construction Fund Support Program” funded by Jeonbuk National University in 2019.


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Copyright information

© The Microbiological Society of Korea 2019

Authors and Affiliations

  • Jinjong Myoung
    • 1
    Email author
  • Jeong Yoon Lee
    • 1
  • Kang Sang Min
    • 1
  1. 1.Korea Zoonosis Research Institute, Genetic Engineering Research Institute and Department of Bioactive Material ScienceJeonbuk National UniversityJeonjuRepublic of Korea

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