eIF2α酸化-ATF4轴介导的转录重编程在ER应激过程中减轻了线粒体损伤
Hien Thi Le1, Jiyoung Yu2, Hee Sung Ahn3
1School of Biological Sciences, University of Ulsan, Ulsan 44610, Korea.
Molecules and cells
|January 5, 2025
概括
eIF2α酸化-ATF4通路对于在内质网膜应激期间维持线粒体健康至关重要. 这个轴调节关键的转录因子,确保细胞平衡和克服压力.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 线粒体生物学 线粒体生物学
背景情况:
- 细胞内膜网膜 (ER) 的压力触发了未展开的蛋白质反应通路.
- eIF2α酸化是ER压力期间细胞平衡的关键调节者.
- 对于eIF2α酸化在线粒体平衡的转录调节中的作用仍然不清楚.
研究的目的:
- 研究eIF2α酸化-ATF4轴在ER压力期间维持线粒体平衡中的作用.
- 为了确定由这个轴调节的下游转录因子.
- 了解对线粒体功能和动态的影响.
主要方法:
- 使用了eIF2α缺乏酸化 (A/A) 的细胞.
- 分析了线粒体动力学,DNA复制和氧化酸化蛋白质表达.
- 在ER压力条件下评估线粒体功能.
- 研究了ATF4过度表达的影响.
主要成果:
- 在ER压力期间,eIF2α酸化缺陷细胞显示线粒体动力学,DNA复制和功能受损.
- 在A/A细胞中,氧化酸化复合蛋白的表达下降.
- 激活转录因子4 (ATF4) 轴对于表达转录因子,如核因素红色素2相关因子2 (NRF2) 和其向基因至关重要.
- 过度表达ATF4在A/A细胞中挽救了线粒体平衡缺陷.
结论:
- 在ER压力期间,eIF2α酸化-ATF4轴对于转录调节线粒体平衡至关重要.
- 这一途径通过重新编程与线粒体功能相关的基因表达来确保细胞适应.
- 这些发现突出了维持在压力下细胞弹性的一个关键机制.
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