title: Hepatitis B virus X protein modulates remodelling of minichromosomes             related to hepatitis B virus replication in HepG2 cells.
abstract: Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is organised             into minichromosomes by histone and non-histone proteins. Remodelling of minichromosomes             is crucial for the regulation of HBV replication, which is dependent on the presence             of the hepatitis B virus X protein (HBx). However, the mechanisms of HBx-dependent             HBV replication remain obscure. The objective of this study was to investigate             the mechanism of HBx-dependent HBV replication through the pathway of chromatin             remodelling. The role of HBx was investigated by transfecting human HepG2 cells             with the linear full-length HBV genome (wild-type) or HBx-deficient mutant HBV DNA             (HBx mutant). Our results showed that although the formation of cccDNA was not             affected by HBx, HBV replication, transcription and antigen secretion were all             significantly reduced, resulting from the absence of HBx. The acetylation, mono-methylation             and phosphorylation of cccDNA-bound histone H3 were associated with HBV replication.             In addition, the levels of cccDNA-bound methylated, phosphorylated and acetylated             histone H3 decreased sharply in HBx mutant HBV DNA. HBx modulated not only the             status of acetylation but also the methylation and phosphorylation of histone             H3 bound to the cccDNA during HBV replication in HepG2 cells. These findings suggest             that HBx plays an important role in modulating the remodelling of minichromosomes             related to HBV replication and it may regulate viral replication through the pathway             of chromatin remodelling.
authors.affiliation: Department of Gastroenterology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Luo
authors.forename: Shu
authors.initials: S
authors.lastname: Chen
authors.forename: Qian
authors.initials: Q
authors.lastname: Gong
authors.forename: Na
authors.initials: N
authors.lastname: Luo
authors.forename: Yu
authors.initials: Y
authors.lastname: Lei
authors.forename: Jinjun
authors.initials: J
authors.lastname: Guo
authors.forename: Song
authors.initials: S
authors.lastname: He
mesh_terms: D000107:Acetylation; D015139:Blotting, Southern; D042002:Chromatin Assembly and Disassembly; D002877:Chromosomes, Human / Q000235:genetics; D004270:DNA, Circular / Q000235:genetics*; D004279:DNA, Viral / Q000235:genetics; D056945:Hep G2 Cells; D006515:Hepatitis B virus / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D008745:Methylation; D010766:Phosphorylation; D010957:Plasmids; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D054334:Viral Regulatory and Accessory Proteins; D014779:Virus Replication
chemical_list: D004270:DNA, Circular; D004279:DNA, Viral; D006657:Histones; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein