通过β-冠状病毒非结构蛋白1对核糖体结合和宿主翻译抑制的进化保存策略
Stephanie F Maurina1, John P O'Sullivan1, Geetika Sharma1
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
Journal of molecular biology
|September 3, 2023
概括
来自SARS-CoV-2和其他β冠状病毒 (β-CoV) 的非结构性蛋白1 (Nsp1) 抑制宿主基因表达. 只有β-CoV Nsp1通过核糖体结合抑制翻译,提供潜在的治疗点.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 非结构蛋白1 (Nsp1) 是SARS-CoV-2的关键致病因子.
- Nsp1通过结合核糖体和抑制翻译来抑制宿主基因表达和抗病毒信号.
- Nsp1还诱导宿主mRNAs的降解.
研究的目的:
- 调查Nsp1-依赖宿主在冠状病毒中关闭的保存和多样化的机制.
- 确定由β-CoV Nsp1.1结合的核糖体的结构基础.
- 了解Nsp1 C终端域 (CTD) 的功能作用及其与N终端效应域的相互作用.
主要方法:
- 来自不同冠状病毒的NSP1序列和结构的比较分析.
- 对Nsp1-CTD与核糖体相互作用的分子建模.
- 功能性试验用于评估翻译抑制和宿主关闭机制.
主要成果:
- 保持NSP1依赖宿主关闭,但只有β-CoVNSP1通过核糖体结合抑制翻译.
- 在NSP1CTD赋予高亲和力核糖体结合,由保存的氨基酸和表面电荷驱动.
- Nsp1核糖体结合域是一个低效的抑制剂;CTD可能会招募N端效应器域.
- 一个病毒RNA元素微调SARS-CoV-2 Nsp1功能,但不是相关病毒的功能.
结论:
- 在冠状病毒中,NSP1表现出不同的核糖体结合和翻译抑制策略.
- 在β-CoV Nsp1 CTD中保存的结构特征介于核糖体结合.
- Nsp1的功能是由病毒RNA元素调节的,这表明了同进化适应.
- 了解NSP1机制可以为针对SARS-CoV-2和其他病原性β-CoVs的治疗策略提供信息.
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