以外核糖酶为媒介的mRNA转录终止的结构基础
Yuan Zeng1,2, Hong-Wei Zhang1,2, Xiao-Xian Wu1
1Key Laboratory of Synthetic Biology, National Key Laboratory of Plant Design, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.
Nature
|March 28, 2024
概括
研究人员发现了酵母中mRNA转录终止的结构机制. 外核酶Rat1与RNA聚合酶II (Pol II) 相互作用,有效地结束转录,这是基因表达至关重要的过程.
科学领域:
- 分子生物学
- 结构生物学
- 遗传学
背景情况:
- 有效的基因转录需要精确地终止RNA合成.
- 细胞利用一种被保护的外核糖酶介导的途径,通过RNA聚合酶II (Pol II) 来终止信使RNA (mRNA) 的转录.
研究的目的:
- 阐明Saccharomyces cerevisiae中的外核糖酶Rat1介导的mRNA转录终止的结构基础.
- 想象Rat1及其合作伙伴Rai1与Pol II转录复合体之间的相互作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定Pol II前终结转录复合物的结构.
- 对Rat1-Rai1-Pol II复合物的高分辨率结构分析.
主要成果:
- 两个冷EM结构揭示了Rat1如何取代Spt5延长因子以结合Pol II茎域.
- Rat1 积极屏蔽 Pol II RNA 出口通道,将新生 RNA 导向其活性部位,并堆叠三个核酸.
- 结构动态显示Rat1在RNA缩短过程中向Pol II旋转.
结论:
- 这项研究提供了由酵母中 Pol II 介导的 Rat1 转录的详细结构机制.
- 这些发现提供了对真核细胞中保存的外核核酶介导终止机制的见解.
相关概念视频
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