RNA聚合酶I的结构和转录调节
Christoph Engel1, Sarah Sainsbury, Alan C Cheung
1Gene Center and Department of Biochemistry, Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany.
Nature
|October 25, 2013
概括
研究人员揭示了酵母RNA聚合酶I的晶体结构,揭示了其无活性和活性状态如何调节转录. 这提供了对核糖体生物发生和细胞生长控制的见解.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 通过RNA聚合酶I (Pol I) 的核糖体RNA转录启动的核糖体生物发生对于真核细胞生长至关重要.
- 了解Pol I的结构和调节是理解这种基本细胞过程的关键.
研究的目的:
- 为了确定酵母菌Saccharomyces cerevisiaeRNA聚合酶I的高分辨率晶体结构.
- 阐明Pol I激活和转录调节的基础结构机制.
主要方法:
- 在2.8 Å分辨率的X射线晶体学.
- 对590千多,14个亚单元的酶结构的分析.
- 与RNA聚合酶II结构的比较.
主要成果:
- 晶体结构揭示了不活跃的Pol I.中不同的"扩展器"和"连接器"元素.
- "扩展器"占据了DNA模板的位置,稳定了扩展的活跃中心裂.
- "连接器"调解二元化,稳定一个不活跃的状态.
- 激活需要脱离这些元素,使裂收缩和转录启动.
- 核心架接口中的一个复合活性位点控制着RNA合成和终结.
结论:
- 该研究揭示了聚合酶调节的新机制,涉及非活性 (扩展) 和活性 (收缩) 状态之间的结构变化.
- 这种结构性理解提供了对核糖体生物发生和真核细胞生长调节的见解.
- 这些发现表明,这种扩展到合同状态的转换可能是转录监管的一般机制.
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