通过真核生物Pol α-原酶进行原料合成的分子舞蹈谱
Zuanning Yuan1, Roxana Georgescu2, Huilin Li3
1Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.
Nature communications
|June 21, 2023
概括
细胞聚合酶α (Pol α) 使用大动作将RNA原始物从Primase 1 (Pri1) 传递给Pol1. 这种由cryo-EM揭示的机制限制了DNA合成期间的原料长度.
科学领域:
- 分子生物学分子生物学
- 生物化学 生化学
- 结构生物学 结构生物学
背景情况:
- 细胞DNA复制的启动需要由聚合酶α (Polα) 合成的初始剂.
- 聚α包括负责DNA聚合酶和RNA原酶活动的子单元.
- 波拉的准交付和长度测定的精确机制仍然难以捉摸.
研究的目的:
- 阐明酵母Polα在原料合成和交付期间的结构动态.
- 了解DNA延伸过程中RNA原料长度是如何调节的.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 可视化酵母Pol α.
- 分析多种状态:apo,原料启动,延长,移交和DNA延伸.
主要成果:
- 化EM显示了Pol α在功能周期期间的显著构造变化.
- 一个关键运动显示Pol1-core从Pri1.1.中接管RNA原始的3'-end.
- 料长度限制与酶和聚合酶子单元的灵活附着有关,诱导压力.
结论:
- 酵母Polα利用大规模的形状变化来进行RNA原料合成和转移.
- 在初始延伸过程中产生的结构灵活性和应力作为长度控制的内置机制.
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