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Updated: Feb 1, 2026

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Growth of Mycobacterium tuberculosis Biofilms
Published on: February 15, 2012
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在mycobacterium tuberculosis中转录启动期间暂停的结构基础
Litao Zheng1, Ke Xu2
1Shanghai Key Laboratory of Anesthesiology and Brain Functional Modulation, Clinical Research Center for Anesthesiology and Perioperative Medicine, Translational Research Institute of Brain and Brain-like Intelligence, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China. zlt22@tongji.edu.cn.
Nature communications
|January 30, 2026
概括
细菌RNA聚合酶在转录启动过程中因RNA-DNA硬质冲突而暂停. 这种结构洞察力揭示了调节基因表达的检查点机制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 细菌RNA聚合酶 (RNAP) 在转录启动过程中经常停顿.
- 这些短暂停顿背后的精确结构机制尚未完全理解.
研究的目的:
- 为了阐明转录启动暂停在Mycobacterium结核病的结构基础.
- 调查 σ 因子和转录因子 CarD 在调节 RNAP 暂停中的作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定高分辨率结构.
- 通过各种DNA架构获得了暂停启动复合体 (PIC) 和启动复合体 (IC) 的结构.
主要成果:
- 冷-EM结构揭示了在6-7 nt阶段的类似暂停的中间体,由新生RNA和σ3.2区域之间的硬质障碍驱动.
- 这种碰撞诱导RNAP结构模块旋转和转录泡紧缩, σ4域重新排列表明了逃脱前状态.
- 补充重建证实了观察到的中间体的生理相关性.
结论:
- 转录启动涉及一个机械检查点,由RNA诱导的 conformational 动力学调节.
- 提出了一种新的RNA诱导模型,用于RNAP在早期转录期间暂停和调节RNAP.
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