拥抱异质性:挑战复合体作为决定性机器的范式
Jacob S Lewis1, Antoine M van Oijen2, Lisanne M Spenkelink2
1Macromolecular Machines Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom.
Chemical reviews
|November 16, 2023
概括
细胞系统,就像DNA复制机器 (replisome),表现出固有的随机性,而不仅仅是决定性的行为. 了解这种变异性是理解复杂生物过程的关键.
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 结构生物学
背景情况:
- 细胞系统作为决定性机器的传统观点正受到新证据的挑战.
- 随机性或随机性在生物过程中起着重要作用,特别是在多蛋白质复合体中.
- DNA复制系统 (replisome) 是一个复杂的组件,对DNA复制至关重要,传统上被视为一个高度有序的机器.
研究的目的:
- 用DNA复制系统作为模型探索多蛋白质复合体的随机行为.
- 审查了解复原体的动态性质的最新进展.
- 突出结构生物学家和生物物理学家研究动态分子组件的挑战和未来方向.
主要方法:
- 对最近关于DNA复制变异性的实验证据的审查.
- 讨论研究动态生物过程的单分子方法.
- 对单粒子冷电子显微镜 (cryo-EM) 数据的分析,以深入了解复制体动力学.
主要成果:
- 最近的研究揭示了DNA复制过程中的显著变异性和异质性.
- 单分子和冷EM技术为复制体的动态性提供了前所未有的洞察力.
- 在DNA复制过程中,复制体在各种形状和组成状态之间进行过渡.
结论:
- DNA复制系统 (复制体) 表现出固有的随机性,挑战细胞机械的决定性模型.
- 了解复原体组装,激活和进展的动态级联对结构生物学提出了新的挑战.
- 从研究动态复制体中学到的原则可以应用于细胞系统中的其他多蛋白质复合体.
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