泛素化蛋白质的降解路径选择

Selection of degradation pathways for ubiquitinated proteins

关键词:  泛素蛋白酶体系统  自噬  泛素化  蛋白质降解

Key words:  ubiquitin proteasome system  autophagy  ubiquitin  protein degradation

摘要:

泛素蛋白酶体系统（ubiquitin proteasome system，UPS）和自噬是细胞内蛋白质降解的两大主要机制，主要通过及时降解折叠、损伤和不需要的蛋白质来维持细胞内蛋白质稳定。在这两个系统中泛素化都是降解信号，但是泛素化蛋白质能够精确地被定位于其中一个路径去降解。细胞是如何调控泛素化蛋白质在这两个系统之间穿梭的，引起了众多学者的关注。泛素化链不同的类型和结构最初被认为在这一过程中发挥了关键作用，但是越来越多的研究表明，还存在其他因素影响泛素化蛋白质的降解路径选择，如泛素受体的寡聚形式、蛋白质的翻译后修饰、伴侣蛋白以及N端精氨酸修饰等。本文总结了UPS和自噬两个蛋白降解途径的具体机制，并重点对影响泛素化蛋白质降解路径选择的研究进展进行综述。

Abstract:

The ubiquitin proteasome system (UPS) and autophagy are the two major intracellular protein degradation pathways. Ubiquitination serves as the degradation signal in both systems, and substrates are precisely targeted to one or the other pathway. The regulation of ubiquination shuttling between two degradation pathways has attracted the attention of many scholars. Different types and structures of ubiquitination chains were initially considered to play a key role in this process, but more and more studies have shown that there are other factors affecting the selection of ubiquitination substrates, such as oligomerization of ubiquitin receptors, post-translational modification of proteins, chaperone protein and N-terminal arginine modification. This paper reviews ubiquitination regulation in UPS and autophagy process.