SARS-CoV-2 多蛋白表达和双膜囊泡的诱导
Meng Zhao1, Yajie Zhang1, Yakun Liang2
1Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai, China.
Journal of virology
|November 6, 2025
概括
严重急性呼吸道综合征冠状病毒2型 (SARS-CoV-2) 非结构性蛋白6 (nsp6) 对于形成双膜囊泡 (DMVs) 是必不可少的. 一个新的代孕系统揭示了nsp6
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 冠状病毒重塑宿主细胞膜,形成双膜囊泡 (DMV). 这些DMV是病毒RNA复制和通过复制-转录复合体 (RTC) 转录的关键平台.
- 关于DMV组装和RTC组件招募的精确机制尚未完全理解.
- 众所周知,非结构性蛋白 (nsps) 3和4对于初始的DMV形成和孔隙组合至关重要.
研究的目的:
- 为研究重症急性呼吸道综合征冠状病毒2型 (SARS-CoV-2) 诱导的双膜囊泡 (DMV) 形成和复制-转录复合体 (RTC) 招募开发代用表达系统,独立于病毒复制.
- 剖析特定SARS-CoV-2非结构蛋白 (nsps) 在DMV生物发生和RTC局部化中的作用.
- 研究nsp6在DMV形成中的膜相关元件 (MAE) 的功能.
主要方法:
- 建立了一个使用SARS-CoV-2多来诱导宿主细胞中的DMV形成的代孕表达系统.
- 通过表达各种nsps组合 (例如,nsp3-4,nsp3-8,nsp3-10) 形成的特征DMV.
- 在细胞透后使用蛋白酶K (PK) 保护试验评估了RTC组件的局部化和膜关联.
主要成果:
- 与nsp3-4.4相比,nsp3-8和nsp3-10多蛋白的表达导致了更大,更异质的DMV.
- 发现Nsps5,7和8与DMV丰富的膜分离物相关,对蛋白酶K消化有部分保护,这表明它们位于DMV内部或附近.
- 在nsp6的膜相关元件 (MAE) 中的突变扰乱了nsp5的处理,废除了DMV的形成,并导致了内分泌网膜 (ER) 异常.
结论:
- 代孕表达系统对于研究冠状病毒诱导的膜重塑和RTC招募是有效的.
- Nsp6在DMV生物发生过程中发挥着关键和必不可少的作用,特别是通过其MAE.
- 这些发现为冠状病毒如何操纵宿主膜进行病毒复制提供了机械的见解.
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