线粒体DNA断裂激活了集成的应激反应,以恢复平衡
Yi Fu1, Olivia Sacco2, Emily DeBitetto2
1Skirball Institute of Biomolecular Medicine, Cell Biology Department, NYU School of Medicine, New York, NY 10016, USA; Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
Molecular cell
|October 13, 2023
概括
线粒体DNA双链断裂 (mtDSBs) 触发了人体细胞的综合应激反应 (ISR). 这种ISR对于维护线粒体功能和DNA损伤后的基因组稳定性至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 线粒体生物学 线粒体生物学
- 遗传学 是一个遗传学.
背景情况:
- 线粒体DNA双链断裂 (mtDSBs) 可能导致基因组降解和拷贝数量的减少.
- 人类细胞对mtDSBs的细胞反应尚未完全阐明.
- 了解mtDSB反应对于线粒体健康和疾病至关重要.
研究的目的:
- 在人类细胞中研究细胞对线粒体DNA双链断裂 (mtDSBs) 的细胞反应.
- 确定参与对mtDSBs反应的关键信号通路.
- 探索特定蛋白质在调解mtDSBs的细胞后果中的作用.
主要方法:
- 使用线粒体向限制酶诱导mtDSBs.
- 评估线粒体功能,包括蛋白质进口,呼吸系统复合体和膜潜力.
- 电子显微镜用于线粒体的超结构分析.
- 综合应激反应 (ISR) 途径的分析,包括eIF2α酸化.
- 蛋白质组分析以确定相互作用的蛋白质.
主要成果:
- mtDSBs导致缺陷的线粒体蛋白质进口,减少呼吸复合体,以及膜潜力的损失.
- 通过电子显微镜观察了改变的线粒体膜和状物超结构.
- mtDSBs通过DELE1和HRI介导的eIF2α酸化激活了综合应激反应 (ISR).
- 抑制ISR加剧了线粒体缺陷,并延迟了mtDNA恢复.
- ATAD3A被确定为潜在的关键蛋白质,从受损的mtDNA向内线粒体膜传递信号.
结论:
- mtDSBs触发了连接受损线粒体基因组与细胞质的级联.
- 综合应激反应 (ISR) 在基因组不稳定期间在维护线粒体平衡中发挥着重要作用.
- ATAD3A可能是细胞对mtDSBs反应的关键调解者.
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