通过STING诱导干扰素需要将其转移到晚期内分泌体
Chenyao Wang1, Nikhil Sharma1, Patricia M Kessler1
1Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
Traffic (Copenhagen, Denmark)
|September 2, 2023
概括
对于先天免疫来说,STING蛋白在后期内分泌体的局部化,而不是Tyr245酸化,是关键. 这一发现澄清了cGAS/STING路径.
科学领域:
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 哺乳动物细胞使用先天免疫通路,包括cGAS/STING通路,通过合成抗菌蛋白来对抗微生物感染.
- cGAS/STING通路识别细胞质DNA,触发信号级联,最终导致I型干扰素和细胞因子的产生.
- 通过cGAMP激活STING (干扰素基因刺激器),导致其寡合化和转位,从而启动下游信号传输.
研究的目的:
- 调查STING Tyr245酸化或其局部化到晚期内基因组是否对IRF3招募和随后的干扰素诱导至关重要.
- 阐明控制STING介导的先天性免疫反应的精确机制.
主要方法:
- 使用药理抑制剂,针对特定的蛋白质贩运步骤.
- 采用基因切除技术去除涉及STING贩运的关键蛋白质.
- 评估STING在各种实验条件下招募IRF3并诱导干扰素生产的能力.
主要成果:
- 证明STING在晚期内体膜中的存在足以进行IRF3介导的干扰素诱导.
- 表明Tyr245对STING的酸化对IRF3的招募和干扰素的生产并不重要.
- 突出了STING的内体位在激活先天免疫信号传递中的关键作用.
结论:
- 在Tyr245中,STING局部化到晚期内分泌体,而不是其酸化状态,是启动IRF3依赖干扰素诱导的关键因素.
- 这一发现完善了我们对cGAS/STING通路在先天免疫中的信号机制的理解.
- 这项研究强调了蛋白质贩运在调节免疫反应中的重要性.
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