title: Hepatitis B virus X protein induces apoptosis by enhancing translocation of Bax to mitochondria.
abstract: Hepatitis B virus X protein (HBx) is essential for viral replication and plays an important role in viral pathogenesis. HBx transactivates many viral and cellular genes and participates in cellular signal transduction pathways, proliferation, and apoptosis. In the present study, we report that HBx induces apoptosis by enhancing the translocation of Bax to mitochondria, followed by inducing the loss of mitochondrial membrane potential and release of cytochrome C. In addition, Bcl-2, inhibitor of Bax, rescues the disruption of mitochondrial membrane potential and DNA fragmentation induced by serum starvation in HepG2-X cells expressing HBx. We also found that HBx binds directly to Bax and interferes with the interaction between Bax and 14-3-3epsilon to enhance the translocation of Bax to mitochondria. Taken together, our data suggest that HBx induces apoptosis by interacting with Bax and enhancing its translocation to mitochondria.
authors.affiliation: Department of Microbiology, School of Bioscience and Biotechnology, Chungnam National University, Daejeon 305-764, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Sang Yong
authors.initials: SY
authors.lastname: Kim
authors.forename: Jinchul
authors.initials: J
authors.lastname: Kim
authors.forename: Heemin
authors.initials: H
authors.lastname: Lee
authors.forename: Misun
authors.initials: M
authors.lastname: Choi
authors.forename: Jeong Ki
authors.initials: JK
authors.lastname: Kim
authors.forename: Jeong Keun
authors.initials: JK
authors.lastname: Ahn
mesh_terms: D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D002454:Cell Differentiation; D002460:Cell Line; D045744:Cell Line, Tumor; D053938:DNA Fragmentation; D006801:Humans; D008564:Membrane Potentials; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D021381:Protein Transport; D015534:Trans-Activators / Q000378:metabolism / Q000502:physiology*; D014162:Transfection; D054334:Viral Regulatory and Accessory Proteins; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
chemical_list: D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; D051028:bcl-2-Associated X Protein; C057628:hepatitis B virus X protein; D053148:Caspase 3