eIF1和eIF5动态控制翻译开始站点保真
Rosslyn Grosely1, Carlos Alvarado1, Ivaylo P Ivanov2
1Dept. of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA.
bioRxiv : the preprint server for biology
|July 19, 2024
概括
细胞启动因子eIF1和eIF5协调蛋白质合成开始地点的选择. 它们独特的结合动态确保了准确的翻译启动,防止了蛋白质身份和功能的错误.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 翻译启动对于蛋白质合成至关重要,并且受到严格监管.
- 翻译启动的失调与各种人类疾病有关.
- 细胞启动因子 (eIFs),包括eIF1和eIF5,在开始地点选择中发挥关键作用.
研究的目的:
- 研究eIF1和eIF5在人类翻译启动过程中的实时功能.
- 阐明eIF1和eIF5在确保准确的开始地点选择方面的作用.
- 了解eIF1和eIF5动态是如何被RNA序列和细胞水平调节的.
主要方法:
- 单分子光分析在体外复制的人类翻译启动.
- 实时监测eIF1和eIF5对信使RNA的结合动态.
- 在纤维化分析中,包括eIF1和eIF5.5的淘汰和过度表达.
主要成果:
- eIF1离开43S启动复合体是快速的,并取决于启动地点,因替代地点或更长的5'UTR而造成延迟.
- eIF1动态采样启动复合体,在替代启动地点进行长时间采样.
- eIF5在启动晚期暂时结合,需要一个启动位点,并通过替代位点抑制.
结论:
- eIF1和eIF5在翻译启动中表现出对立的角色,控制开始站点选择的准确性.
- eIF1和eIF5的多个绑定事件精确地调节了开始位置的准确性.
- 根据细胞条件,微调eIF1和eIF5水平的翻译启动忠实度.
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