通过线粒体未折叠蛋白反应维护和传播有害的线粒体基因组
Yi-Fan Lin1, Anna M Schulz1, Mark W Pellegrino1
1Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA.
Nature
|May 3, 2016
概括
线粒体DNA (mtDNA) 缺失导致细胞功能障碍. 线粒体未折叠蛋白响应 (UPR) 激活ATFS-1,这令人惊地传播了这些有害的mtDNA删除.
科学领域:
- 细胞生物学
- 遗传学
- 线粒体生物学
背景情况:
- 线粒体基因组 (mtDNA) 编码重要的氧化酸化 (OXPHOS) 蛋白质.
- 积累mtDNA删除导致细胞功能障碍,并与衰老和Kearns-Sayre综合征等疾病有关.
- 由ATFS-1介导的线粒体展开蛋白反应 (UPR) 是细胞对OXPHOS缺陷的防御.
研究的目的:
- 调查ATFS-1在异性质Caenorhabditis elegans模型中的有害mtDNA删除的维持和传播中的作用.
- 了解细胞如何管理mtDNA异质体和相关的OXPHOS功能障碍.
主要方法:
- 采用了异形状的Caenorhabditis elegans菌株,其中包括野生型mtDNA和3. 1基基mtDNA删除 (∆mtDNA).
- 评估ATFS-1损伤在构成性UPR (mt) 激活的情况下对∆mtDNA的百分比的影响.
- 在不同的实验条件下量化mtDNA删除水平.
主要成果:
- 异质细胞菌株呈现了60%的∆mtDNA,适度的线粒体功能障碍和构成性UPR () 激活.
- 影响ATFS-1显著降低了∆mtDNA百分比的十倍,降至7%.
- 这表明ATFS-1在维护或传播有害mtDNA方面发挥作用.
结论:
- 由mtDNA异质体中的OXPHOS缺陷引发的UPR(mt) 激活可能通过ATFS-1传播有害的mtDNA.
- 这种传播似乎是通过促进线粒体生物发生和动态来恢复OXPHOS功能.
- ATFS-1 是细胞对mtDNA删除的反应和潜在传播的一个关键因素.
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