用三叶草RNA启动的病毒基因组复制的结构基础
Keerthi Gottipati1,2, Sean C McNeme1, Jerricho Tipo3
1Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA.
Nucleic acids research
|July 24, 2023
概括
肠道病毒使用5'三叶草RNA结构作为分子开关. 这种结构与宿主多C结合蛋白2 (PCBP2) 和病毒3CDpro相互作用,控制病毒翻译和基因组复制之间的过渡.
科学领域:
- 病毒学 病毒学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 阳性链RNA病毒基因组编码蛋白质翻译和复制机制.
- 肠道病毒利用5'三叶草RNA结构来调节翻译和复制之间的切换.
- 这种切换涉及与宿主多C结合蛋白2 (PCBP2) 和病毒3CDpro蛋白的相互作用.
研究的目的:
- 确定来自Coxsackievirus和小儿麻症病毒的肠道病毒三叶草RNA的结构.
- 阐明三叶草RNA作为病毒复制分子开关的机制.
- 调查 A•C-U 基三重和 PCBP2 结合位点在调节此开关中的作用.
主要方法:
- 用X射线晶体学来确定三叶草RNA结构.
- 生物物理测试用于评估蛋白质-RNA相互作用和结合亲缘关系.
- 对RNA折叠,基配对和蛋白质结合接口的结构分析.
主要成果:
- 三叶草RNA折叠成一个H型四路结,由独特的AC-U基三重稳定.
- PCBP2结合点在空间上是近接的,与3CDpro结合点不同.
- A•C-U 基三重体限制了三叶草的灵活性,部分阻断了 PCBP2 的结合;其消除增强了 PCBP2 的亲和力.
结论:
- 提出了一种新的机制模型,用于作为分子开关的肠道病毒三叶草RNA.
- A•C-U基三重体在调节PCBP2结合和翻译复制开关方面发挥着至关重要的作用.
- 结构洞察力为了解肠道病毒中的病毒复制控制提供了基础.
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