流感聚合酶的共同转录帽抢夺机制
Alexander Helmut Rotsch1, Delong Li1,2, Maud Dupont3
1Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Goettingen, Germany.
Nature
|March 4, 2026
概括
流感病毒的 cap-dependent mRNA 生产依赖于由病毒RNA-dependent RNA聚合酶 (FluPol) 的 cap snatching. 冷-EM结构揭示了FluPol如何与宿主RNA聚合酶II相互作用,分裂并获得用于病毒转录的封闭RNA片段.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 结构生物学是结构生物学.
背景情况:
- 流感病毒mRNA需要5'盖结构以保持稳定性,核出口和翻译.
- 这种帽子结构是通过一种称为帽子抢夺的过程获得的,这种过程由病毒RNA依赖RNA聚合酶 (FluPol) 介导.
- 帽子抢夺涉及FluPol与宿主RNA聚合酶II (Pol II)及其新生转录的相互作用.
研究的目的:
- 阐明导致流感病毒上限依赖的mRNA合成的分子机制.
- 确定FluPol,宿主Pol II和帽子抢夺期间的延长因子之间的相互作用的结构基础.
- 提供原子层面的洞察力,了解帽子捕获过程的裂变前和裂变后的状态.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定关键蛋白质复合物的结构.
- 获得的结构是FluPol结合转录Pol II与延长因子DSIF在分离前状态.
- 在帽子抢劫事件发生后,第二个结构捕获了该综合体.
主要成果:
- 我们可视化了FluPol,宿主Pol II和DSIF之间的直接相互作用,将FluPol内核酶定位在Pol IIRNA退出通道附近.
- 这些相互作用对FluPol的内核酶活性及其在宿主细胞内的功能至关重要.
- 分裂后的结构揭示了FluPol内部分裂的封闭RNA的重新排列,促进其作为病毒转录的原始材料的使用.
结论:
- 这项研究提供了对流感病毒所使用的共同转录捕获机制的详细分子见解.
- 结构数据澄清了FluPol如何劫持宿主转录机制以启动病毒RNA合成.
- 了解这些机制对于开发针对流感病毒复制的抗病毒策略至关重要.
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