在SARS-CoV-2上的一种RGD基因刺激TGF-β信号传递并降低干扰素的调节
Nicholas P Gracie1, Anupriya Aggarwal2, Rachel Luo1
1School of Life and Environmental Sciences, The University of Sydney, Camperdown, New South Wales, Australia.
Journal of virology
|September 4, 2025
概括
SARS-CoV-2 的尖端蛋白
科学领域:
- 病毒学
- 免疫学
- 分子生物学
背景情况:
- 严重急性呼吸系统冠状病毒2 (SARS-CoV-2) 使用其尖端 (S) 蛋白进入细胞.
- 众所周知,S蛋白还可以激活各种细胞信号通路.
- RGD (Arg-Gly-Asp) 基因是已知的整合素复合体的配体.
研究的目的:
- 研究SARS-CoV-2 S蛋白激活TGF-β信号的分子机制.
- 确定RGD动机和整合素复合物的作用.
- 阐明S蛋白诱导的TGF-β信号对细胞抗病毒防御的影响.
主要方法:
- 使用了复合S蛋白,伪型病毒和病毒感染的细胞.
- 研究了TGF-β通路的激活,包括依赖SMAD3的PAI-1表达.
- 使用突变的S蛋白RGD动机和RGD抗剂ATN-161来评估整合素的作用.
- 测量IFN-β表达以评估抗病毒防御的破坏.
主要成果:
- 在SARS-CoV-2 S蛋白的RBD中RGD动机诱导TGF-β细胞因子的表达.
- TGF-β通路的激活需要ACE2并导致SMAD3依赖的PAI-1表达.
- 用ATN-161破坏RGD动机或阻塞取消了TGF-β信号,涉及整合素.
- 通过TGF-β抑制IFN-β的表达,从而降低抗病毒免疫力.
结论:
- 在SARS-CoV-2 S蛋白中的RGD基因对于通过整合素复合体激活TGF-β信号至关重要.
- 通过抑制IFN-β和阻碍抗病毒防御,这种激活导致免疫抑制.
- S蛋白-整合素信号轴代表了SARS-CoV-2感染和长期COVID (PASC) 的潜在治疗目标.
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