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单个凝聚分子通过两个不同的机制产生力量
Georgii Pobegalov1,2, Lee-Ya Chu1, Jan-Michael Peters3
1The Francis Crick Institute, London, NW1 1AT, UK.
Nature communications
|July 4, 2023
概括
凝聚蛋白复合体通过形成循环来组织DNA. 这项研究揭示了单个凝聚素分子如何通过不同的机械机制产生力,为DNA组织提供了洞察力.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 结构生物学是结构生物学.
背景情况:
- 凝聚蛋白复合体对于DNA空间组织和循环挤出至关重要.
- 凝聚素作为一个分子机器的精确机械运作在很大程度上是未知的.
研究的目的:
- 为了研究在构造变化过程中单个凝聚分子产生的机械力.
- 阐明凝聚力产生和DNA相互作用背后的分子机制.
主要方法:
- 使用单分子力测量来量化机械力.
- 采用分子动态模拟来模拟凝聚素-DNA相互作用和能量储存.
主要成果:
- 由热波动驱动的Cohesin的SMC卷轴曲,可以抵抗高达1pN (~32nm位移) 的力.
- 依赖ATP的凝聚性头部接触发生在单个步骤 (~10 nm) 中,抵御高达15 pN的力.
- 分子动力学模拟显示,NIPBL在头部参与过程中储存能量,并在脱离时释放能量.
结论:
- 单个凝聚分子通过两个不同的机制产生力:热波动驱动的曲和依赖ATP的头部接触.
- 一个拟议的模型解释了这些力量产生能力如何促进凝聚性-DNA相互作用和DNA循环挤出.
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