内核酶G通过选择性增加线粒体tRNAThr生产来促进肝脏线粒体呼吸
Xihui Xu1, Rozhin Penjweini2, Lóránt Székvölgyi3
1Laboratory of Obesity and Aging Research, Cardiovascular Branch, National Heart Lung and Blood Institute, NIH, Bethesda, MD 20892.
概括
线粒体内核酶G (EndoG) 对于男性肝脏健康至关重要,通过调节线粒体tRNA生产来促进呼吸. EndoG 缺乏会损害这一过程,导致男性的代谢功能障碍相关的脂肪性肝病 (MASLD).
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 代谢疾病 代谢疾病
背景情况:
- 已知线粒体内核酶G (EndoG) 在亡过程中降解DNA.
- EndoG 缺乏导致线粒体功能障碍,这表明线粒体内在发挥作用.
- 与代谢功能障碍相关的脂肪性肝病 (MASLD) 涉及线粒体功能障碍,在男性中更为普遍.
研究的目的:
- 阐明EndoG调节线粒体功能的机制.
- 调查EndoG在MASLD病原发生中的作用,特别是在男性中.
- 了解EndoG如何影响线粒体呼吸和tRNA产生.
主要方法:
- 在MASLD肝脏中研究EndoG表达.
- 利用光终身成像显微镜来评估线粒体的氧气消耗.
- 在小鼠模型中检查了EndoG缺乏和mt-tRNAThr补充的效果.
主要成果:
- 缺少EndoG会降低MASLD肝脏,导致疾病独立于肥胖,但只在男性.
- EndoG解决了线粒体tRNA/DNA混合体,并促进了mt-tRNAThr的产生.
- 缺少EndoG可选择性地消除高氧耗费的线粒体,这种缺陷可以通过mt-tRNAThr补充来逆转.
结论:
- EndoG通过调节mt-tRNAThr生产来促进线粒体呼吸,这对男性肝脏健康至关重要.
- EndoG的失调通过 mitochondrial 功能受损,导致男性特异性的 MASLD.
- 针对EndoG介导的tRNA调节可能为MASLD提供治疗策略.
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