SARS-CoV-2的Orf9b蛋白调节了线粒体蛋白质生物发生
Svenja Lenhard1, Sarah Gerlich2,3, Azkia Khan1
1Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany.
The Journal of cell biology
|September 8, 2023
概括
SARS-CoV-2 病毒蛋白质 Orf9b 通过准 Tom70.0. 破坏了线粒体蛋白质的进口. 这导致线粒体蛋白质的枯竭和线粒体体积的减少,影响细胞功能.
科学领域:
- 细胞生物学 细胞生物学
- 病毒学 病毒学
- 线粒体生物学 线粒体生物学
背景情况:
- 严重急性呼吸道综合征冠状病毒2 (SARS-CoV-2) 使用Orf9b蛋白与线粒体外膜蛋白Tom70.0.相互作用.
- Tom70对于将蛋白质导入线粒体至关重要,并在细胞的抗病毒防御中发挥作用.
- 除了对抗病毒信号的干扰外,Orf9b对线粒体生物发生的确切影响仍然不清楚.
研究的目的:
- 为了研究SARS-CoV-2 Orf9b蛋白对线粒体蛋白质进口和生物生成的影响.
- 为了确定Orf9b是否直接影响线粒体蛋白质组调节.
- 阐明Tom70在Orf9b介导的线粒体改变中的作用.
主要方法:
- 在人类HEK293细胞中,SARS-CoV-2 Orf9b的表达.
- 利用复制的酵母系统研究人类Tom70功能,独立于抗病毒反应.
- 分析了线粒体蛋白质水平和线粒体体积.
主要成果:
- Orf9b表达导致人体细胞中特定的线粒体蛋白质耗尽,特别是在呼吸细胞中.
- 酵母系统证实Orf9b表达导致某些线粒体蛋白质的选择性下降.
- 在酵母模型中观察到Orf9b表达时,线粒体体积的总体减少.
结论:
- SARS-CoV-2 Orf9b直接影响线粒体Tom70-依赖蛋白质的进口.
- 该病毒可以通过Orf9b与Tom70.0.的相互作用来调节线粒体蛋白质组.
- 这种相互作用影响线粒体功能和生物发生,独立于抗病毒反应途径.
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