title: Stronger activation of SREBP-1a by nucleus-localized HBx.
abstract: We previously showed that hepatitis B virus (HBV) X protein activates the sterol regulatory element-binding protein-1a (SREBP-1a). Here we examined the role of nuclear localization of HBx in this process. In comparison to the wild-type and cytoplasmic HBx, nuclear HBx had stronger effects on SREBP-1a and fatty acid synthase transcription activation, intracellular lipid accumulation and cell proliferation. Furthermore, nuclear HBx could activate HBV enhancer I/X promoter and was more effective on up-regulating HBV mRNA level in the context of HBV replication than the wild-type HBx, while the cytoplasmic HBx had no effect. Our results demonstrate the functional significance of the nucleus-localized HBx in regulating host lipogenic pathway and HBV replication.
authors: VIDO-InterVac, Veterinary Microbiology, University of Saskatchewan, Saskatoon, Canada.
authors: Qi
authors: Q
authors: Wu
authors: VIDO-InterVac, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors: Ling
authors: L
authors: Qiao
authors: Drug Discovery Group, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors: Jian
authors: J
authors: Yang
authors: VIDO-InterVac, Veterinary Microbiology, Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors: Yan
authors: Y
authors: Zhou
authors: VIDO-InterVac, Veterinary Microbiology, Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. Electronic address: qiang.liu@usask.ca.
authors: Qiang
authors: Q
authors: Liu
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D017931:DNA Primers; D006515:Hepatitis B virus / Q000235:genetics; D006801:Humans; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051780:Sterol Regulatory Element Binding Protein 1 / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D015854:Up-Regulation; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D051780:Sterol Regulatory Element Binding Protein 1; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein
keywords: Cell proliferation; Fatty acid synthase; HBV enhancers/promoters and replication; HBx; Lipid accumulation; SREBP-1a