延长因子EF-G和EF-Tu与23SRNA中保存循环的相互作用
D Moazed1, J M Robertson, H F Noller
1Thimann Laboratories, University of California, Santa Cruz 95064.
Nature
|July 28, 1988
概括
延长因子EF-G和EF-Tu在细菌蛋白质合成过程中与核糖体RNA (rRNA) 相互作用. EF-G在rRNA位置1.067和2.660附近结合,而EF-Tu则在2.660位置附近相互作用.
科学领域:
- 分子生物学分子生物学
- 核糖体功能 核糖体功能
- 细菌蛋白质合成 细菌蛋白质合成
背景情况:
- 延长因子EF-Tu和EF-G对于蛋白质合成至关重要,分别调解tRNA传递和转位.
- 这两种因素都与核糖体相互作用,是GTPases,但它们与核糖体RNA (rRNA) 的直接相互作用仍然不完全理解.
- 了解这些相互作用是解读翻译机制和潜在药物点的关键.
研究的目的:
- 研究延长因子EF-G和EF-Tu与大肠杆菌中的核糖体RNA的直接相互作用.
- 用化学探测绘制这些因子在23SrRNA上的特定结合点.
- 将这些结合部位与已知的功能区域和抗生素相互作用部位相关联.
主要方法:
- 利用化学探测技术检测23SrRNA上的因子依赖的"足迹".
- 使用大肠杆菌核糖体进行了体外和体内实验.
- 分析了与已知rRNA的功能部位相关的足迹位置.
主要成果:
- 在23S rRNA上观察到EF-G依赖的足迹,位置为1.067 (域II) 和位置为2.660 (域VI) 左右.
- EF-Tu显示了体外足迹的重叠位置2655和2661,但在位置1067没有检测到相互作用.
- 已识别的1,067个区域已知可以结合抗生素斯特和蛋白质L11,而2,660个区域则是阿尔法-沙和辛等细胞毒素的目标.
结论:
- EF-G 与23S rRNA的特定区域直接相互作用,包括列/L11结合点 (1,067) 和普遍保留的循环 (2,660).
- EF-Tu还与23S rRNA的2660区域相互作用,这表明rRNA在调解延长因子功能的作用.
- 这些发现为翻译的结构基础和调节延长因子活动的潜在机制提供了洞察力.
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