机械化学力量调节停滞不前的新生链的组成和命运
Danish Khan1, Ananya A Vinayak1, Cole S Sitron2
1Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305, USA.
bioRxiv : the preprint server for biology
|August 12, 2024
概括
机械化学力量在与核糖体相关的质量控制过程中调节了CAT尾部. 这个过程在挤出和释放模式之间切换,以管理新生的多链,防止蛋白质毒性聚合.
科学领域:
- 分子生物学分子生物学
- 蜂质量控制 蜂质量控制
- 蛋白质合成 蛋白质合成
背景情况:
- 核糖体相关质量控制 (RQC) 途径解决了蛋白质合成期间核糖体停滞的问题.
- 一个关键的RQC机制涉及以mRNA独立的方式将C端氨基酸 (CAT) 尾部附加到停滞的新生链 (NCs).
- 包括氨酸 (Ala) 和氨酸 (Thr) 在内的CAT尾部成分的功能意义仍然不清楚.
研究的目的:
- 调查CAT尾部组成及其在RQC途径中的功能之间的关系.
- 阐明控制CAT尾巴的监管机制及其在新生的多链管理中的作用.
主要方法:
- 使用酵母作为模型系统,采用生物化学方法.
- 研究了机械化学力量在CAT尾部过程中对新生的多链的影响.
- 分析了CAT尾部成分 (Ala,Thr) 对挤出和释放过程的影响.
主要成果:
- 作用于新生链的机械化学力量调节了CAT尾部.
- CAT尾巴以"挤出模式"运行,以提高氨酸在无处不在的可访问性,Thr防止低效的聚氨结构.
- 拉力将CAT尾部切换到"Ala-only释放模式"后的ubiquitination,促进NC释放和降解;未能切换导致聚合.
结论:
- 对于高效的RQC来说,CAT尾部的组成及其由机械化学力量的调节至关重要.
- 双模式 (挤出/释放) CAT尾部机制确保正确处理停滞的新生链,防止蛋白质毒性.
- 这种开关的调节失调导致错误折叠的蛋白质和细胞损伤的积累.
关键词:
在CAT尾巴上.机械化学 机械化学蛋白质折叠 蛋白质的折叠蛋白质质量控制 蛋白质质量控制核糖体的核糖体是指核糖体中的核糖体.核糖体拖延时间核糖体相关质量控制 (RQC)翻译翻译翻译翻译翻译翻译更多相关视频
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