在抑制PKR激活的综合应激反应效应方面,SARS-CoV-2变种特异性差异
Wanda Christ1, Jonas Klingström2, Janne Tynell3
1Center for Infectious Medicine, Department of Medicine Huddinge, Karolinska Institutet. Stockholm, Sweden.
Virus research
|November 18, 2023
概括
SARS-CoV-2 感染激活了综合应激反应 (ISR),但抑制了其下游效应. 不同的变种,如Delta和Omicron,独特地影响ISR激活和压力颗粒形成.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 细胞应激反应的应激反应
背景情况:
- 综合应激反应 (ISR) 对于细胞防御病毒感染至关重要.
- 众所周知,SARS-CoV-2会干扰细胞通路,包括压力颗粒 (SG) 的形成.
- 对SARS-CoV-2与ISR相互作用的精确机制仍然不完全理解.
研究的目的:
- 为了研究SARS-CoV-2感染如何激活ISR通路.
- 描述ISR激活在受感染细胞中的下游效应.
- 为了比较不同SARS-CoV-2变种的ISR激活和SG形成.
主要方法:
- 分析ISR激活标记物,包括PKR和eIF2α酸化.
- 量化感染细胞中转化停止和应激颗粒形成的量化.
- 对ATF4和CHOP转录因子表达的评估.
- 对祖先,三角形和Omicron BA.1 SARS-CoV-2变种的比较分析.
主要成果:
- SARS-CoV-2 感染通过 PKR 激活 ISR,但抑制下游效应,包括 ATF4 和 CHOP 诱导.
- 压力颗粒的形成被抑制,eIF2α酸化对转化停止的作用最小.
- 与祖先菌株相比,SARS-CoV-2的三角形变种显示了较弱的PKR激活.
- 奥米克朗BA.1变种表现出更高的p-eIF2α水平和显著增加的SG形成.
结论:
- SARS-CoV-2 不同调节ISR通路,影响细胞功能.
- 在ISR激活和SG形成的变体特异性差异可能会影响SARS-CoV-2的发病性.
- 了解这些相互作用对于开发针对SARS-CoV-2的有效治疗策略至关重要.
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