title: Hepatitis B virus X protein enhances activation of nuclear factor κB through interaction with valosin-containing protein.
abstract: Hepatitis B virus X protein (HBx protein) is a multifunctional regulatory protein. The transactivation of nuclear factor kappa B (NF-κB) by HBx protein has been shown to be of importance in the pathogenesis of HBV-related diseases. However, the mechanism involved remains largely unclear. In this study, a CytoTrap yeast two-hybrid system was employed to screen binding partners of the HBx protein; 29 cellular proteins, including valosin-containing protein (VCP), were identified. The interaction between HBx protein and VCP was further confirmed in vitro and in vivo using a glutathione S-transferase pull-down assay and co-immunoprecipitation, respectively. It was also shown that this interaction is mediated by amino acid residues 51-120 of the HBx protein. In Huh-7 hepatoma cells, HBx protein enhanced the VCP-mediated activation of NF-κB. Our findings provide new insights into the molecular mechanisms that lead to the activation of NF-κB by HBx protein.
authors.affiliation: Key Laboratory of Ministry of Education for Gastrointestinal Cancer, Research Center of Molecular Medicine, Fujian Medical University, 88 Jiaotong Road, Fuzhou 350004, People's Republic of China.
authors.forename: Bo-Yan
authors.initials: BY
authors.lastname: Jiao
authors.forename: Wan-Song
authors.initials: WS
authors.lastname: Lin
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: She
authors.forename: Wan-Nan
authors.initials: WN
authors.lastname: Chen
authors.forename: Xu
authors.initials: X
authors.lastname: Lin
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006509:Hepatitis B / Q000378:metabolism* / Q000821:virology; D006515:Hepatitis B virus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016328:NF-kappa B / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation; D000074405:Valosin Containing Protein; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D018797:Cell Cycle Proteins; D016328:NF-kappa B; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D000251:Adenosine Triphosphatases; C000614178:VCP protein, human; D000074405:Valosin Containing Protein