使用DNA原形旋转器对基因组处理酶的旋转跟踪
Pallav Kosuri1,2,3, Benjamin D Altheimer1,2,3,4, Mingjie Dai4,5,6
1Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
Nature
|July 19, 2019
概括
研究人员开发了一种新方法,即基于原形旋转器的成像和跟踪 (ORBIT),以准确地实时测量DNA旋转. 这种技术提供了毫秒的分辨率, 提高了我们对DNA修复和转录过程的理解.
科学领域:
- 分子生物学
- 生物物理
- 基因组学
背景情况:
- 转录和复制等基因组处理反应涉及DNA旋转.
- 测量DNA旋转的现有方法缺乏在生理条件下研究许多酶所需的时间分辨率和吞吐量.
研究的目的:
- 引入一种新的高分辨率方法来跟踪单个分子水平的DNA旋转.
- 克服研究DNA与蛋白质相互作用现有技术的局限性.
主要方法:
- 基于原形旋转器的成像和跟踪 (ORBIT) 的开发.
- 使用光标记的DNA原形旋转器来追踪DNA旋转的毫秒分辨率.
- 应用用于研究RecBCD复合物和RNA聚合酶 (RNAP) 的活性.
主要成果:
- ORBIT成功追踪了由RecBCD复合体和RNAP诱导的DNA旋转.
- 详细描述RecBCD介导的解事件,包括启动,转移,暂停和回溯.
- 揭示了RecBCD的启动机制,包括可逆的ATP独立解和RecB电机参与.
- 在RNAP转录过程中直接观察单基对解步骤.
结论:
- ORBIT提供了前所未有的毫秒级别分辨率来跟踪单个分子的DNA旋转.
- 该方法阐明了像RecBCD这样的DNA修复酶和像RNAP这样的转录机制的复杂机制.
- 预计ORBIT将促进对蛋白质与DNA相互作用的更广泛的研究.
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