14个亚单元RNA聚合酶I的晶体结构
Carlos Fernández-Tornero1, María Moreno-Morcillo, Umar J Rashid
11] Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain [2].
Nature
|October 25, 2013
概括
研究人员揭示了酵母RNA聚合酶I (Pol I) 的晶体结构,这是细胞生长的关键酶. 该结构揭示了Pol I如何与DNA相互作用并调节转录,为蛋白质生物合成提供了洞察力.
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:
- 蛋白质生物合成对细胞生长至关重要,并依赖于核糖体.
- 核糖体的产生取决于核糖体RNA (rRNA) 的合成.
- RNA聚合酶I (Pol I) 是负责rRNA生成的真核酶.
研究的目的:
- 为了确定Saccharomyces cerevisiaeRNA聚合酶I的高分辨率晶体结构.
- 阐明PoI活动和监管的结构性基础.
主要方法:
- 采用X射线晶体学来确定酵母Pol I的结构.
- 该结构的分辨率为3.0 Å分辨率.
主要成果:
- 晶体结构显示出一个紧的Pol I核心,有一个宽的DNA结合裂和一个稳定的茎.
- 在DNA结合裂内的延伸循环可能调节Pol I转录.
- 亚单元A12.2与活性部位相互作用,将类似TFIIS的带插入核酸入口孔中,解释RNA裂变和α-amanitin不敏感性.
- A49-A34.5异构体与亚单元A135相互作用,可能调节A12.2.2.
结论:
- 确定的结构为真核RNA聚合酶I机制提供了前所未有的原子细节.
- 结构洞察力解释了特定子单元在转录,RNA分裂和酶调节中的作用.
- 这项工作为了解Pol I在细胞生长和疾病中的功能奠定了基础.
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