以NEMF为媒介的CAT尾巴为转移相关的质量控制提供了便利
Amanda Ennis1, Lihui Wang1, Yue Xu1
1Laboratory of Molecular Biology, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
The Journal of cell biology
|April 21, 2025
概括
细胞通过不同的途径降解停滞的蛋白质. 不间断的mRNA翻译蛋白通过一种新的ER关联降解 (ERAD) 途径被降解,包括Golgi检索和NEMF介导的尾巴.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质的生物发生.
背景情况:
- 在内分泌网膜 (ER) 的同翻译转位过程中,核糖体停滞可能导致转位膜堵塞.
- 损伤的ER蛋白质生物发生是由转位孔堵塞造成的.
- 转位关联质量控制 (TAQC) 是一种鲜为人知的过程,它解决了哺乳动物细胞中转位塞的问题.
研究的目的:
- 阐明转位相关质量控制 (TAQC) 过程背后的分子机制.
- 为了区分各种TAQC基质的降解途径.
- 确定参与新生蛋白质链质量控制的关键因素.
主要方法:
- 在全基因组的CRISPR屏幕上.
- 活细胞成像成像技术
- 对蛋白质降解途径 (溶酶体,蛋白质体,ERAD) 的分析.
主要成果:
- 来自具有核糖体阻滞多元A序列的mRNA的TAQC基质被溶酶体和蛋白质体降解.
- 来自nonstop (NS) mRNA的缺陷新生链通过非传统的ER相关蛋白降解 (ERAD) 途径降解.
- 这种ERAD途径涉及ER-to-Golgi贩运,KDEL介导的Golgi检索,以及tRNA结合因子NEMF.
- 在NEMF中,NEMF将容易聚合的碳酸尾连接到停滞不前的NS新生链上,称为CAT尾.
结论:
- 通过Golgi检索,NEMF介导的CAT尾矿针对ERAD的TAQC基板的一个子集.
- 这种新的途径通过清除缺陷的新生链路来维护ER稳态.
- 该研究揭示了TAQC基质的独特降解路径,突出了ER中蛋白质质量控制的复杂性.
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