异构结复合体与停滞的核糖体和缓慢的翻译独立解体的关联
Olivier Bensaude1, Isabelle Barbosa2, Lucia Morillo2
1Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, Paris, France. bensaude@bio.ens.psl.eu.
Nature communications
|May 17, 2024
概括
异子结合复合体 (EJCs) 形成稳定的mRNP与停滞的核糖体. 虽然取决于翻译的分解是快速的,但大多数稳定状态的EJC被独立于翻译删除,具有转录特定的寿命.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 基因规则 基因规则
背景情况:
- 在mRNA剪接过程中,外因子结合复合体 (EJCs) 沉积.
- 众所周知,EJC的目标是通过无意中介衰变来降解异常转录.
- 对于EJC去除的机制和动力学,特别是转化独立的途径,人们对其了解甚微.
研究的目的:
- 研究EJC组装和拆卸的动力学和转录特异性.
- 探索EJC与核糖体和mRNP的关联.
- 揭示欧洲司法委员会监管的新机制.
主要方法:
- 使用核心EJC子单元的分裂纳米化酶标记用于定量测试.
- 雇员转录和翻译逮捕实验.
- 进行深度RNA测序以分析EJC结合的转录及其寿命.
主要成果:
- EJCs形成大型,稳定的信使核糖蛋白复合体 (mRNP),其中包括停滞的核糖体.
- 新存入的EJC主要通过依赖翻译的机制 (85%) 移除.
- 在稳定状态下,由于更快的动力学,只有30%的EJC需要翻译才能拆卸.
- 结合EJC的转录显示了对微管和中心体基因的偏差,转录特定的EJC寿命.
结论:
- EJCs表现出一种动态的行为,与核糖体形成稳定的关联.
- 翻译依赖和独立的机制都对EJC去除有所贡献,在不同的细胞时间尺度上有不同的贡献.
- 转录特异性结合和循环表明EJCs在无意中介衰变之外的调节作用,可能与微管和中心体功能有关.
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