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细胞质TOP3α促进了通过cGAS的线粒体DNA传感
Dongjing Cai1,2, Cheng Chen2,3, Piyanat Meekrathok1,2
1Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, 410008, China.
EMBO reports
|October 31, 2025
概括
细胞质拓聚酶3α (TOP3α) 通过促进cGAS传感来增强线粒体DNA (mtDNA) 触发的先天免疫力. 异常的TOP3α表达或突变会损害这一关键的免疫信号通路.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 线粒体DNA (mtDNA) 激活了天生的免疫力.
- 拓酶3α (TOP3α) 存在于线粒体和细胞核中,其细胞质作用尚不清楚.
- 细胞质TOP3α在免疫中的功能仍然难以捉摸.
研究的目的:
- 阐明细胞质TOP3α在先天性免疫反应中的功能作用.
- 研究TOP3α如何影响线粒体DNA (mtDNA) 释放和cGAS激活.
- 确定TOP3α突变对cGAS介导免疫的影响.
主要方法:
- 细胞测试观察mtDNA聚类和释放.
- 在体外无细胞系统中研究蛋白质-DNA相互作用.
- 对一种罕见的TOP3α突变 (G250D) 的分析及其对蛋白质复合体形成和DNA结合的影响.
主要成果:
- 异常的TOP3α表达通过mPTP-VDAC促进mtDNA释放,激活cGAS.
- 细胞质TOP3α通过cGAS增强mtDNA传感,放大先天免疫信号传递.
- TOP3α 直接增强 mtDNA-cGAS 相互作用,cGAS 竞争 mtDNA 结合.
- TOP3α中的G250D突变破坏了复杂组合,mtDNA结合和cGAS-mtDNA相互作用,损害了免疫力.
结论:
- 细胞质TOP3α作为mtDNA触发的cGAS-STING天生的免疫反应的关键放大器.
- TOP3α与mtDNA的相互作用对于强大的cGAS介导炎症至关重要.
- TOP3α的调节失调或突变可能会损害细胞对炎症刺激的防御机制.
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