title: Calcium signaling by HBx protein in hepatitis B virus DNA replication.
abstract: Hepatitis B virus (HBV) infects more than 300 million people and is a leading cause of liver cancer and disease. The HBV HBx protein is essential for infection; HBx activation of Src is important for HBV DNA replication. In our study, HBx activated cytosolic calcium-dependent proline-rich tyrosine kinase-2 (Pyk2), a Src kinase activator. HBx activation of HBV DNA replication was blocked by inhibiting Pyk2 or calcium signaling mediated by mitochondrial calcium channels, which suggests that HBx targets mitochondrial calcium regulation. Reagents that increased cytosolic calcium substituted for HBx protein in HBV DNA replication. Thus, alteration of cytosolic calcium was a fundamental requirement for HBV replication and was mediated by HBx protein.
authors.forename: M J
authors.initials: MJ
authors.lastname: Bouchard
authors.forename: L H
authors.initials: LH
authors.lastname: Wang
authors.forename: R J
authors.initials: RJ
authors.lastname: Schneider
mesh_terms: D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D020013:Calcium Signaling; D016572:Cyclosporine / Q000494:pharmacology; D003600:Cytosol / Q000378:metabolism; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D004789:Enzyme Activation; D051418:Focal Adhesion Kinase 2; D016679:Genome, Viral; D006515:Hepatitis B virus / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008928:Mitochondria / Q000378:metabolism; D010766:Phosphorylation; D010957:Plasmids; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D054334:Viral Regulatory and Accessory Proteins; D014779:Virus Replication; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D015220:Calcium Channels; D004279:DNA, Viral; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid; D016572:Cyclosporine; D011505:Protein-Tyrosine Kinases; D051418:Focal Adhesion Kinase 2; D019061:src-Family Kinases; D002118:Calcium