终端核糖体RNA螺旋之间的相互作用稳定了E. 大肠杆菌是大型核糖体子单元
Amos J Nissley1, Tammam S Kamal2, Jamie H D Cate3,2,4
1Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA.
概括
在大肠杆菌50S核糖体中的MS2标签通过破坏RNA三级接触来破坏组件的稳定性. 通过向螺旋体H98添加腺来恢复这些相互作用,可以改善核糖体的稳定性,用于结构研究.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 核糖体是重要的核糖蛋白机器,负责蛋白质合成.
- MS2标签通常用于促进核糖体结构和功能的体外研究.
- MS2标签通常被插入到Escherichia coli50S核糖体子单元中的23SrRNA的螺旋H98中.
研究的目的:
- 研究MS2标签插入大肠杆菌50S子单元的螺旋体H98对核糖体稳定性的影响.
- 为了确定任何观察到的不稳定性的分子基础.
- 为结构和功能研究制定改善MS2标记核糖体稳定性的策略.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于可视化核糖体结构.
- 野生类型 (WT) 和MS2标记的50S子单位的生物化学分析.
- 对rRNA序列的遗传操纵.
主要成果:
- 与WT相比,在H98中插入MS2标签会破坏大肠杆菌50S子单元的稳定.
- 不稳定是由于涉及H1,H94和H98.8螺旋体的RNA-RNA三级接触的破坏引起的.
- 在扩展的H98螺旋中插入单个腺可以恢复这些三级接触并提高稳定性.
结论:
- 在大肠杆菌50S亚单元螺旋H98中标记MS2可能会损害核糖体的稳定性.
- 特定的RNA-RNA三级相互作用对于维持50S子单元的稳定性至关重要.
- 优化MS2标签插入策略,如添加腺素,可以提高核糖体稳定性,用于先进的结构和功能研究.
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