Hepatitis B doubly spliced protein, generated by a 2.2 kb doubly spliced hepatitis B virus RNA, is a pleiotropic activator protein mediating its effects via activator protein-1-and CCAAT/enhancer-binding protein-binding sites
Hepatitis B doubly spliced protein, generated by a 2.2 kb doubly spliced hepatitis B virus RNA, is a pleiotropic activator protein mediating its effects via activator protein-1-and CCAAT/enhancer-binding protein-binding sites
复制标题
乙型肝炎双剪接蛋白由 2.2 kb 双剪接乙型肝炎病毒 RNA 生成，是一种多效性激活蛋白，通过激活蛋白 1 和 CCAAT/增强子结合蛋白结合位点介导其作用
DOI：
10.1099/vir.0.022517-0
复制
发表时间：
2010-10-01
影响因子：
3.8
通讯作者：
Lin, Xu
中科院分区：
文献类型：
--
作者：
Chen, Wan-Nan;Chen, Jin-Yan;Lin, Xu
慢性B型肝炎患者血清中常检测到2.2 kb双剪接缺陷型B型肝炎病毒（HBV）基因组。然而，这种类型的缺陷基因组的生物学意义还没有得到很好的理解。在这项研究中，从分离并转染Huh-7肝癌细胞的2.2 kb双剪接缺陷HBV基因组中证实了B型肝炎双剪接蛋白（HBDSP）的表达。为了探索HBDSP的潜在致病性，利用酵母双杂交技术筛选与HBDSP相互作用的肝细胞蛋白。出乎意料的是，HBDSP可以反式激活GAL 4响应元件，缺失图谱显示，位于HBDSP的残基Leu-48和Gln-75之间的片段是至关重要的反式激活活性。在Huh-7肝癌细胞中，HBDSP主要定位于细胞质，并对巨细胞病毒立即早期启动子、猴病毒40增强子/启动子和HBV调控元件（包括S1启动子、S2启动子、增强子I和核心上游调控序列进一步的研究表明，反式激活活性是由激活蛋白-1和CCAAT/增强子结合蛋白-结合位点这些发现提示HBDSP是一种多效性激活蛋白，可能作为HBV毒力因子。
The 2.2 kb doubly spliced defective hepatitis B virus (HBV) genome is frequently detected in the serum of patients with chronic hepatitis B. However, the biological significance of this type of defective genome is not well understood In this study, expression of the hepatitis B doubly spliced protein (HBDSP) was confirmed from the 2.2 kb doubly spliced defective HBV genome, which was isolated and transfected into Huh-7 hepatoma cells. To explore the potential pathogenicity of HBDSP, hepatocellular proteins interacting with HBDSP were screened by a yeast two-hybrid assay. Unexpectedly, HBDSP could transactivate the GAL4-responsive element, and deletion mapping revealed that the fragment located between residues Leu-48 and Gln-75 of HBDSP was crucial for transactivation activity. In Huh-7 hepatoma cells, HBDSP localized predominantly to the cytoplasm and showed transactivating effects on the cytomegalovirus immediate-early promoter, simian virus 40 enhancer/promoter and HBV regulatory elements including the S1 promoter, S2 promoter, Enhancer I and core upstream regulatory sequences Further studies revealed that the transactivating activities were mediated by activator protein-1- and CCAAT/enhancer-binding protein-binding sites These findings suggest that HBDSP is a pleiotropic activator protein that can potentially serve as an HBV virulence factor.