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Updated: Sep 20, 2025

In Vitro Transcribed RNA-based Luciferase Reporter Assay to Study Translation Regulation in Poxvirus-infected Cells

In Vitro Transcribed RNA-based Luciferase Reporter Assay to Study Translation Regulation in Poxvirus-infected Cells

Published on: May 1, 2019

对于特定的宿主和病毒mRNA,在poxvirus诱导的关闭期间会出现不同的非正规翻译启动模式

Chorong Park¹, Aaron J Ferrell², Nathan Meade¹

¹Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.

Nature microbiology

|May 28, 2025

概括

疫苗病毒 (VacV) 宿主关闭通过不同的机制选择性地转化宿主JUN mRNA和病毒mRNA. 核糖体结构揭示了eIF3如何在感染期间重塑40S子单元以实现差异性蛋白质合成.

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:

病毒经常抑制宿主蛋白质合成 (宿主关闭),同时保持自己的翻译.
在病毒感染的后期阶段,维持特定宿主mRNA的翻译机制尚不清楚.

研究的目的:

为了研究某些宿主mRNAs,如JUN,在疫苗病毒 (VacV) 感染期间如何翻译.
阐明核糖体蛋白和启动因子在VacV关闭期间差异mRNA转化中的作用.

主要方法:

RNA测序 (RNAseq) 和多基因组分析分析mRNA翻译.
电子显微镜 (Cryo-EM) 用于确定核糖体结构.
基于细胞的测试来评估蛋白质丰富度.

主要成果:

VacV感染导致多个宿主mRNA的多元体占用率增加,JUN显示蛋白质丰富度增加.
病毒mRNA的翻译,但不是JUN mRNA,需要小核糖体蛋白RACK1和真核细胞启动因子eIF3.
病毒和JUN mRNAs的明显的5'未翻译区域与差异性的eIF3依赖关系相关.
结冷EM检测显示,当结合eIF3时,40S核糖体头域的感染诱导扩大,特别是涉及RACK1.

结论:

宿主被VacV关闭涉及eIF3结合的40S核糖体的重塑,改变它们的旋转动态.
差异化翻译启动策略被用于在波克斯病毒传播期间产生基本宿主 (JUN) 和病毒蛋白质.
这些发现提供了关于核糖体如何适应病毒感染的结构性见解,以选择性地翻译特定的mRNA.

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