强力诱导的融和S-DNA DNA过度拉伸的途径表现出不同的动力学
Vinoth Sundar Rajan1,2, Sune Levin1, Micah J McCauley3
1Department of Life Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
Nucleic acids research
|December 10, 2024
概括
双链DNA (dsDNA) 中的三环细胞因子修饰会影响力诱导过渡到S-DNA. 这些修改改变了过渡力,扩展和自由能量,揭示了S-DNA是快速的,由力产生状态.
科学领域:
- 分子生物物理学 分子生物物理学
- 生物化学 生物化学
- 遗传学 遗传学 是一个
背景情况:
- 细胞对双链DNA (dsDNA) 施加了显著的机械力.
- 高张力导致B-DNA转化为S-DNA和单链DNA (ssDNA).
- S-DNA的特性和生物相关性在很大程度上是未知的.
研究的目的:
- 研究三环氨酸 (tC) 修改对B-DNA转化为S-DNA的影响.
- 描述与这种强力诱导过渡相关的能量,动力学和结构变化.
- 阐明S-DNA在细胞过程中的作用.
主要方法:
- 拉伸60个基对 (bp) dsDNA寡核酸与不同的tC修饰使用光学笔.
- 观察和量化B-DNA和S-DNA之间的合作性,可逆的两种状态过渡.
- 在不同的力量下重建B-to-S过渡的自由能源配置.
主要成果:
- tC 修改增加了 B-DNA 到 S-DNA 过渡所需的力.
- tC 修改减少了过渡的延伸和自由能量,与增加的 DNA 末端磨损相关.
- 观察到B-to-S过渡是快速的,并且依赖于力,比内部dSDNA融化更快.
结论:
- S-DNA是一种完全由机械力诱导的状态.
- B-to-S 过渡是一个快速的过程,与 dsDNA 化不同.
- 在强力介导的DNA链分离过程中,S-DNA可能起到暂时的中间作用,可能涉及分子电机.
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