Real-time analysis of single influenza virus replication complexes reveals large promoter-dependent differences in initiation dynamics.
Real-time analysis of single influenza virus replication complexes reveals large promoter-dependent differences in initiation dynamics.
复制标题
对单一流感病毒复制复合物的实时分析揭示了起始动力学中启动子依赖性的巨大差异。
DOI：
10.1093/nar/gkz313
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发表时间：
2019
影响因子：
14.9
通讯作者：
Robb NC
中科院分区：
文献类型：
--
作者：
Robb NC
流感病毒的病毒RNA（vRNA）基因组由RNA依赖性RNA聚合酶（RNAP）通过互补RNA（cRNA）中间体复制。当被RNAP结合时，vRNA启动子可以采用多种构象。然而，这些构象的动力学，决定因素和生物学作用是未知的;此外，对cRNA启动子构象知之甚少。为了探测初始复制过程中采用的RNA构象，我们实时监测单个表面固定的vRNA和cRNA起始复合物。结果表明，vRNA启动子的3′端处于起始前构象和起始构象的动态平衡，而cRNA启动子的动态平衡非常有限。cRNA启动子近端3′区域的两个残基（vRNA启动子中不存在的残基）允许cRNA模板链进一步到达活性位点，限制了启动子动力学。我们的研究结果突出了流感启动机制中依赖于启动子的差异，并推进了我们对病毒复制的理解。
The viral RNA (vRNA) genome of influenza viruses is replicated by the RNA-dependent RNA polymerase (RNAP) via a complementary RNA (cRNA) intermediate. The vRNA promoter can adopt multiple conformations when bound by the RNAP. However, the dynamics, determinants, and biological role of these conformations are unknown; further, little is known about cRNA promoter conformations. To probe the RNA conformations adopted during initial replication, we monitored single, surface-immobilized vRNA and cRNA initiation complexes in real-time. Our results show that, while the 3′ terminus of the vRNA promoter exists in dynamic equilibrium between pre-initiation and initiation conformations, the cRNA promoter exhibited very limited dynamics. Two residues in the proximal 3′ region of the cRNA promoter (residues absent in the vRNA promoter) allowed the cRNA template strand to reach further into the active site, limiting promoter dynamics. Our results highlight promoter-dependent differences in influenza initiation mechanisms, and advance our understanding of virus replication.