在RNA支架上激活的GTPase运动驱动了共同翻译蛋白的向
Kuang Shen1, Sinan Arslan, David Akopian
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Nature
|December 14, 2012
概括
信号识别粒子 (SRP) RNA充当分子支架,指导SRP-SRP受体复合体运动以精确准蛋白质. 这种基于RNA的机制确保了蛋白质到膜的准确传递.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 细胞生物学 细胞生物学
背景情况:
- 蛋白质定位到膜对于细胞功能至关重要,由信号识别粒子 (SRP) 途径介导.
- 一个核糖核蛋白复合体的SRP,将蛋白质向内细胞网膜或血膜.
- 在这种机制中,延长型SRPRNA的确切作用尚不清楚.
研究的目的:
- 阐明SRPRNA在蛋白向途径中的功能性作用.
- 为了研究SRPRNA上的SRP-SRP受体复合物的动态.
- 了解蛋白质转位启动的调节.
主要方法:
- 使用单分子光显微镜来追踪SRP-SRP受体复合物的运动.
- 研究是使用大肠杆菌系统进行的.
- 研究了核糖体和SecYEG转位子的调节作用.
主要成果:
- SRP-SRP受体GTPase复合体沿着SRPRNA从四环末端到远端移动超过100 Å.
- GTP水解发生在SRPRNA的远端.
- 核糖体负面调节这种运动,而SecYEG转位子在以后积极调节它.
结论:
- SRP RNA 作为一个动态的分子支架,协调蛋白质向的空间和时间准确性.
- 这种RNA介导的机制促进了在核糖体的向和转位机械之间的交换.
- 这些发现表明,RNA支架在调节核糖蛋白复合体动态方面具有更广泛的原理.
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