近距离标记揭示了与人类线粒体进口受体TOMM20相关的RNA结合蛋白
Saira Akram1, Katharina I Zittlau2,3, Karan Sharma4
1Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany.
Journal of proteome research
|December 22, 2025
概括
人类TOMM20是一种线粒体进口受体,优先结合RNA结合蛋白 (RBPs) 和转化因子. 这种相互作用可能有助于通过在线粒体外膜中保留保护性RBP来维持转化应激期间的细胞平衡.
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:
- 线粒体蛋白质进口依赖于外周受体蛋白质,如TOM20和TOM70.
- 虽然在酵母体中进行了研究,但对转基因TOM20和TOM70的相互作用不太了解.
- 与线粒体外膜 (MOM) 的RNA关联和局部翻译的特征较差.
研究的目的:
- 研究人类TOMM20和TOMM70的关联概况.
- 专注于与RNA结合蛋白 (RBPs) 的相互作用,因为有MOMRNA关联和局部翻译的证据.
- 阐明TOMM20和TOMM70在细胞平衡和转化应激中的作用.
主要方法:
- 在HeLa细胞中使用了基于APEX2的近距离标签.
- 为人类TOMM20和TOMM70生成了关联配置文件.
- 在正常和胺素诱导的翻译抑制条件下分析了RBP和翻译因子相互作用.
主要成果:
- 确定了多个RBPs和转换因子与TOMM20相比TOMM70.的优先关联.
- 保护线粒体蛋白mRNA的RBP保护蛋白mRNASYNJ2BP显示出与TOMM20的优先结合.
- 普罗米辛治疗增加了RBP与TOMM20的关联,但不是TOMM70,这表明它在应激反应中发挥了作用.
结论:
- 与TOMM70不同的是,TOMM20可能在转化应激期间在维持细胞平衡中发挥作用.
- 在压力条件下,TOMM20可能会在MOM中保留保护性RBP和与翻译相关的蛋白质.
- 这些发现揭示了人们对MOM RNA关联和局部翻译的理解不佳的过程.
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