比较FRET对,报告细菌核糖体中子单元间旋转
Ananya Das1, Chen Bao1, Dmitri N Ermolenko1
1Department of Biochemistry & Biophysics, School of Medicine and Dentistry, and Center for RNA Biology, University of Rochester, Rochester, NY 14642, United States.
Journal of molecular biology
|June 22, 2023
概括
由延长因子G (EF-G) 驱动的核糖体间子单元旋转,可以在没有GTP水解的情况下自发发生. 这种非旋转和旋转状态之间的自发运动凸显了翻译过程中热驱动的核糖体重排.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- 核糖体转位对于蛋白质合成至关重要.
- 延长因子G (EF-G) 介导着沿着mRNA的核糖体运动.
- 这一过程涉及于核糖体子单元之间的旋转运动.
研究的目的:
- 调查是否需要由EF-G进行GTP水解.
- 为了确定核糖体旋转是否可以自发发生.
- 探索热能在核糖体动力学中的作用.
主要方法:
- 使用了两个独立的Förster共振能量转移 (FRET) 试验.
- 标记的核糖体蛋白质 (bS6,bL9) 和核糖体RNA (rRNAs;16S中的h44,23S中的H101).
- 监控的核糖体构造 (非旋转,旋转,半旋转).
主要成果:
- 确定了三种不同的FRET状态,代表了核糖体构造.
- 在没有EF-G的情况下,证明了自发的子单位间旋转.
- 观察到自发波动在FRET对和实验条件之间有所不同.
结论:
- 核糖体间子单元旋转不仅仅取决于EF-G和GTP的水解.
- 热驱动的大规模核糖体重组在翻译中起着重要作用.
- 使用多个FRET对对于准确研究核糖体动力学是必不可少的.
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