在初始转录中,s70指的位移非常异质,并且依赖于促进体
Anna Wang1,2, Andrew Fletcher3, Pratip Mukherjee4,5
1Biological Physics Research Group, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom.
Nucleic acids research
|September 18, 2025
概括
使用一种新的单分子测定方法监测细菌的西格玛指动态. 西格玛指的移位先于促进体逃逸,时间受促进体序列的影响,影响转录调节.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 遗传学 是一个遗传学.
背景情况:
- 细菌的西格玛因子 (σ) 具有保存的"σ指"模块,对于转录启动至关重要.
- 在DNA相互作用,RNA合成和促进体逃逸中s-指的作用被认为是可行的,但尚未完全理解.
研究的目的:
- 为了研究转录启动和促进器逃逸期间的σ指的动态运动.
- 阐明相对于RNA聚合酶活性 σ指位移的时间和序列.
主要方法:
- 开发和应用一种新型的单分子Förster共振能量转移 (smFRET) 试验.
- 在转录启动和促进器逃逸事件期间实时监控s-指的运动.
主要成果:
- 观察到 σ 指位移发生在所有测试的促进体中促进体逃脱之前.
- 相对于与新生RNA发生碰撞的s-指位移的时间有所不同.
- 确定了σ指位移动力学中的促体特异性差异,影响了整体转录动力学.
结论:
- σ指在转录启动和促进体逃逸中发挥着动态作用.
- 促进子序列显著影响 σ 指动力学和转录调节.
- 涉及类似结构模块的类似机制可能存在于不同的生命王国.
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