对SARS-CoV-2 Nsp4和宿主细胞ESCRT蛋白质的编排诱导了内细胞网膜的形态变化
Allison Kifer1, Franciso Pina1, Nicholas Codallos1
1School of Biological Sciences, Department of Molecular Biology, NSB, University of California, San Diego, San Diego, CA 92093-0377.
Molecular biology of the cell
|February 12, 2025
概括
严重急性呼吸道综合征冠状病毒2 (SARS-CoV-2) 非结构性蛋白4 (Nsp4) 单独诱导了病毒复制所必需的内分泌网膜 (ER) 重组. 这些变化涉及输送 (ESCRT) 途径的内体组分复合体,而不是规范的UPR或ERSU组件.
科学领域:
- 病毒学 病毒学
- 细胞生物学 细胞生物学
- 分子机制的分子机制
背景情况:
- 严重急性呼吸道综合征冠状病毒2 (SARS-CoV-2) 非结构性蛋白质 (Nsp3,Nsp4,Nsp6) 重组宿主细胞内膜网膜 (ER),形成用于病毒复制的双膜囊泡 (DMV).
- 了解每个Nsp的具体作用以及ER重塑背后的机制对于抗病毒策略至关重要.
研究的目的:
- 剖析SARS-CoV-2非结构蛋白在ER重组中的功能性作用.
- 阐明病毒复制过程中ER形态变化背后的分子机制.
主要方法:
- 利用酵母Saccharomyces cerevisiae和人类细胞实验系统来研究NSP功能.
- 研究了NSP4表达对ER结构,展开蛋白质反应 (UPR) 和ER监测 (ERSU) 途径的影响.
主要成果:
- 仅Nsp4就足以引发显著的ER结构变化.
- Nsp4表达激活了UPR和ERSU,但ER形态变化独立于正规的UPR/ERSU组件.
- 在酵母中,ER重塑是由体内分类复合物用于运输 (ESCRT) 蛋白Vps4和Vps24的介导.
结论:
- Nsp4是SARS-CoV-2引起的ER重组的一个关键驱动因素.
- ESCRT途径,而不是正规的UPR/ERSU,在NSP4介导的ER形态变化中起着至关重要的作用.
- 人体细胞中NSP4诱导的ER变化验证了研究ESCRT参与DMV形成的最小系统.
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