Department of Virology II, National Institute of Infectious Diseases, Tokyo 162-8640, Japan.
Virology. 2011 Feb 5;410(1):38-47. doi: 10.1016/j.virol.2010.10.026. Epub 2010 Nov 18.
To identify the host factors implicated in the regulation of hepatitis C virus (HCV) genome replication, we performed comparative proteome analyses of HCV replication complex (RC)-rich membrane fractions prepared from cells harboring genome-length bicistronic HCV RNA at the exponential and stationary growth phases. We found that the eukaryotic chaperonin T-complex polypeptide 1 (TCP1)-ring complex/chaperonin-containing TCP1 (TRiC/CCT) plays a role in the replication possibly through an interaction between subunit CCT5 and the viral RNA polymerase NS5B. siRNA-mediated knockdown of CCT5 suppressed RNA replication and production of the infectious virus. Gain-of-function activity was shown following co-transfection with whole eight TRiC/CCT subunits. HCV RNA synthesis was inhibited by an anti-CCT5 antibody in a cell-free assay. These suggest that recruitment of the chaperonin by the viral nonstructural proteins to the RC, which potentially facilitate folding of the RC component(s) into the mature active form, may be important for efficient replication of the HCV genome.
为了确定宿主因素在丙型肝炎病毒（HCV）基因组复制调控中的作用，我们对在指数生长期和静止期细胞中富含 HCV 复制复合物（RC）的膜部分进行了比较蛋白质组分析，这些细胞含有全长双顺反子 HCV RNA。我们发现，真核伴侣蛋白 T 复合物 1（TCP1）-环复合物/含 TCP1 的伴侣蛋白（TRiC/CCT）在复制中发挥作用，可能通过亚基 CCT5 与病毒 RNA 聚合酶 NS5B 之间的相互作用。siRNA 介导的 CCT5 敲低抑制了 RNA 复制和感染性病毒的产生。通过共转染整个八个 TRiC/CCT 亚基显示出功能获得活性。在无细胞测定中，抗 CCT5 抗体抑制 HCV RNA 合成。这表明病毒非结构蛋白将伴侣蛋白募集到 RC 中，这可能有助于 RC 成分折叠成成熟的活性形式，这对于 HCV 基因组的有效复制可能很重要。
