线粒体功能障碍导致通过铁硫团缺陷导致核基因组不稳定
Joshua R Veatch1, Michael A McMurray, Zara W Nelson
1Division of Basic Sciences, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, WA 98109, USA.
Cell
|July 1, 2009
概括
线粒体功能障碍,而不是呼吸不足,导致酵母菌的核基因组不稳定. 这种不稳定性与铁硫生物发生障碍有关,这对DNA完整性至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 线粒体生物学 线粒体生物学
背景情况:
- 线粒体DNA (mtDNA) 突变和核基因组不稳定性与人类疾病有关.
- 线粒体功能与核基因组完整性之间的关系尚未完全理解.
研究的目的:
- 研究Saccharomyces cerevisiae中线粒体功能障碍和核基因组不稳定性之间的联系.
- 阐明mtDNA丢失影响核基因组完整性的机制.
主要方法:
- 在酵母中诱导线粒体DNA损失.
- 细胞周期进展和基因组不稳定性的分析.
- 评估线粒体膜潜力和铁硫 (ISC) 生物发生.
- 基因操纵以降低非线粒体ISC蛋白质合成的调节.
主要成果:
- 丢失mtDNA引发了细胞危机,其特点是细胞循环停止和核基因组不稳定.
- 这种危机与线粒体膜潜力减少有关,而不仅仅是呼吸不存在.
- 在线粒体功能障碍期间发现了铁硫 (ISC) 生物发生的缺陷.
- 单独降低非线粒体ISC蛋白质合成的调节导致健康细胞的基因组不稳定性.
结论:
- 线粒体功能障碍,特别是减少了膜潜力,刺激了核基因组的不稳定性.
- 损坏的ISC生物发生是这种不稳定性的关键媒介,影响核基因组完整性至关重要的蛋白质.
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