由冠状病毒引起的NSP1介导的翻译关闭的普遍特征
Katharina Schubert1, Evangelos D Karousis2, Ivo Ban1
1Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich 8049, Switzerland.
Molecular cell
|October 6, 2023
概括
冠状病毒使用NSP1蛋白来阻止宿主蛋白质的产生. 这项研究揭示了病毒中保存的NSP1功能,解释了病毒RNA转化如何被选择性启用.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 结构生物学 结构生物学
背景情况:
- 非结构性蛋白1 (Nsp1) 是一种关键的冠状病毒毒性因子,抑制宿主蛋白质合成.
- SARS-CoV-2 Nsp1 C端域通过阻断核糖体mRNA通道来抑制翻译.
- 在各种冠状病毒中,NSP1介导的翻译抑制和选择性病毒RNA翻译的机制仍然不完全理解.
研究的目的:
- 为了研究NSP1功能在不同冠状病毒中的保存机制.
- 阐明NSP1的N-终端和C-终端域在宿主转化抑制中的作用.
- 了解Nsp1如何促进病毒RNAs的优先翻译.
主要方法:
- 结构生物学 (X射线结晶学,冷EM)
- 生物物理技术 (例如,SPR,ITC) 的使用
- 生物化学试验 (例如,体外翻译,核糖体结合试验)
- 变异性研究的研究.
主要成果:
- 证实了Nsp1 C-终端域在SARS-CoV-2,MERS-CoV和Bat-Hp-CoV中具有保留的抑制作用.
- 发现蝙蝠-Hp-CoV Nsp1的N终端域与40S核糖体子单元的解码中心结合,可能阻断mRNA和eIF1A.
- 基于结构的分析强调了解码中心相互作用对Nsp1功能和所有研究的冠状病毒中选择性病毒RNA转化的关键作用.
结论:
- Nsp1采用涉及N-终端和C-终端域的保存机制来调节宿主和病毒翻译.
- Nsp1与核糖体解码中心的相互作用对其抑制功能和选择性病毒RNA翻译至关重要.
- 这项研究为Nsp1在冠状病毒感染期间对蛋白质合成的多方面的控制提供了一个机制框架.
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