Department of Gastroenterology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
J Gen Virol. 2010 May;91(Pt 5):1207-12. doi: 10.1099/vir.0.016907-0. Epub 2010 Jan 6.
The hepatitis C virus NS5B RNA-dependent RNA polymerase (RdRp) is a key enzyme involved in viral replication. Interaction between NS5B RdRp and the viral RNA sequence is likely to be an important step in viral RNA replication. The C-terminal half of the NS5B-coding sequence, which contains the important cis-acting replication element, has been identified as an NS5B-binding sequence. In the present study, we confirm the specific binding of NS5B to one of the RNA stem-loop structures in the region, 5BSL3.2. In addition, we show that NS5B binds to the complementary strand of 5BSL3.2 (5BSL3.2N). The bulge structure of 5BSL3.2N was shown to be indispensable for tight binding to NS5B. In vitro RdRp activity was inhibited by 5BSL3.2N, indicating the importance of the RNA element in the polymerization by RdRp. These results suggest the involvement of the RNA stem-loop structure of the negative strand in the replication process.
丙型肝炎病毒 NS5B RNA 依赖性 RNA 聚合酶（RdRp）是参与病毒复制的关键酶。NS5B RdRp 与病毒 RNA 序列的相互作用可能是病毒 RNA 复制的重要步骤。NS5B 编码序列的 C 末端包含重要的顺式作用复制元件，已被鉴定为 NS5B 结合序列。在本研究中，我们证实了 NS5B 与该区域内一个 RNA 茎环结构（5BSL3.2）的特异性结合。此外，我们还表明 NS5B 结合到 5BSL3.2 的互补链（5BSL3.2N）上。5BSL3.2N 的突环结构对于与 NS5B 的紧密结合是必不可少的。体外 RdRp 活性被 5BSL3.2N 抑制，表明该 RNA 元件在 RdRp 聚合中的重要性。这些结果表明负链的 RNA 茎环结构参与了复制过程。
