26S蛋白酶体组装的分子机制研究

Molecular Mechanisms of the Assembly of 26S Proteasome

26S蛋白酶体广泛分布于真核细胞中的胞质和胞核,主要是由20S核心复合物(coreparticle,CP)和19S调节复合物(regulatory particle,RP)组成,它负责细胞大多数蛋白质的降解,在几乎所有生命活动中具有关键的调控作用。26S蛋白酶体的组装是一个非常复杂且高度条理的过程,不同的分子伴侣,如PAC1-4、Ump1、p27、p28和s5b等,参与其中发挥识别及调节作用,以确保高效准确地完成蛋白酶体的组装。本文系统总结分析了20S核心复合物和19S调节复合物的组装过程及调控机制的最近研究进展。

The 26S proteasome is composed of one 20S catalytic core particle and one or two 19S regulatory particles,it is widely distributed in the nucleus and cytoplasm of eukaryotic cell.The 26S proteasome is responsible for degradation of most ubiquitylated proteins in the cell,playing critical regulatory roles in nearly all the biological processes.The assembly of 26S proteasome is a complicated and highly coordinated process,assembly of 20S CP and 19S RP is accompanied by several proteasome-dedicated chaperons,including PAC1-4,Ump1,p27,p28,s5b and so on.These chaperons function as crucial adaptors for efficient and accurate proteasome assembly.In this review,we summarize recent advances in the multistep assembly process and regulatory mechanisms of 26S proteasome.