title: Hepatocyte Factor JMJD5 Regulates Hepatitis B Virus Replication through Interaction with HBx.
abstract: Hepatitis B virus (HBV) is a causative agent for chronic liver diseases such as hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). HBx protein encoded by the HBV genome plays crucial roles not only in pathogenesis but also in replication of HBV. Although HBx has been shown to bind to a number of host proteins, the molecular mechanisms by which HBx regulates HBV replication are largely unknown. In this study, we identified jumonji C-domain-containing 5 (JMJD5) as a novel binding partner of HBx interacting in the cytoplasm. DNA microarray analysis revealed that JMJD5-knockout (JMJD5KO) Huh7 cells exhibited a significant reduction in the expression of transcriptional factors involved in hepatocyte differentiation, such as HNF4A, CEBPA, and FOXA3. We found that hydroxylase activity of JMJD5 participates in the regulation of these transcriptional factors. Moreover, JMJD5KO Huh7 cells exhibited a severe reduction in HBV replication, and complementation of HBx expression failed to rescue replication of a mutant HBV deficient in HBx, suggesting that JMJD5 participates in HBV replication through an interaction with HBx. We also found that replacing Gly(135) with Glu in JMJD5 abrogates binding with HBx and replication of HBV. Moreover, the hydroxylase activity of JMJD5 was crucial for HBV replication. Collectively, these results suggest that direct interaction of JMJD5 with HBx facilitates HBV replication through the hydroxylase activity of JMJD5.
  
  
  OBJECTIVE
  HBx protein encoded by hepatitis B virus (HBV) plays important roles in pathogenesis and replication of HBV. We identified jumonji C-domain-containing 5 (JMJD5) as a novel binding partner to HBx. JMJD5 was shown to regulate several transcriptional factors to maintain hepatocyte function. Although HBx had been shown to support HBV replication, deficiency of JMJD5 abolished contribution of HBx in HBV replication, suggesting that HBx-mediated HBV replication is largely dependent on JMJD5. We showed that hydroxylase activity of JMJD5 in the C terminus region is crucial for expression of HNF4A and replication of HBV. Furthermore, a mutant JMJD5 with Gly(135) replaced by Glu failed to interact with HBx and to rescue the replication of HBV in JMJD5-knockout cells. Taken together, our data suggest that interaction of JMJD5 with HBx facilitates HBV replication through the hydroxylase activity of JMJD5.
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Kouwaki
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Okamoto
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Ayano
authors.initials: A
authors.lastname: Ito
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Sugiyama
authors.affiliation: Laboratory of System Immunology, World Premier International Research Center Immunology Frontier Research Center, Osaka University, Osaka, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamashita
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Kusakabe
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Junki
authors.initials: J
authors.lastname: Hirano
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Takasuke
authors.initials: T
authors.lastname: Fukuhara
authors.affiliation: Department of Microbiology, Faculty of Medicine, University of Yamanashi, Yamanashi, Japan.
authors.forename: Atsuya
authors.initials: A
authors.lastname: Yamashita
authors.affiliation: DNA-Chip Developmental Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Saito
authors.affiliation: DNA-Chip Developmental Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Okuzaki
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Watashi
authors.affiliation: The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Sugiyama
authors.affiliation: The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan.
authors.forename: Sachiyo
authors.initials: S
authors.lastname: Yoshio
authors.affiliation: Laboratory of System Immunology, World Premier International Research Center Immunology Frontier Research Center, Osaka University, Osaka, Japan Laboratory of Integrated Biological Information, Institute for Virus Research, Kyoto University, Kyoto, Japan.
authors.forename: Daron M
authors.initials: DM
authors.lastname: Standley
authors.affiliation: The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kanto
authors.affiliation: The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizokami
authors.affiliation: Department of Microbiology, Faculty of Medicine, University of Yamanashi, Yamanashi, Japan.
authors.forename: Kohji
authors.initials: K
authors.lastname: Moriishi
authors.affiliation: Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan matsuura@biken.osaka-u.ac.jp.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Matsuura
mesh_terms: D019943:Amino Acid Substitution; D002460:Cell Line; D055786:Gene Knockout Techniques; D006515:Hepatitis B virus / Q000502:physiology*; D022781:Hepatocytes / Q000821:virology*; D056466:Histone Demethylases / Q000235:genetics / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D006801:Humans; D016297:Mutagenesis, Site-Directed; D025941:Protein Interaction Mapping; D015534:Trans-Activators / Q000378:metabolism*; D054334:Viral Regulatory and Accessory Proteins; D014779:Virus Replication
chemical_list: D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D056466:Histone Demethylases; C550342:KDM8 protein, human