Molecular mechanisms of proteasome assembly.

Laboratory of Protein Metabolism, Department of Integrated Biology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Nature Reviews Molecular Cell Biology (Impact Factor: 36.46). 03/2009; 10(2):104-15. DOI: 10.1038/nrm2630
Source: PubMed

ABSTRACT The 26S proteasome is a highly conserved protein degradation machine that consists of the 20S proteasome and 19S regulatory particles, which include 14 and 19 different polypeptides, respectively. How the proteasome components are assembled is a fundamental question towards understanding the process of protein degradation and its functions in diverse biological processes. Several proteasome-dedicated chaperones are involved in the efficient and correct assembly of the 20S proteasome. These chaperones help the initiation and progression of the assembly process by transiently associating with proteasome precursors. By contrast, little is known about the assembly of the 19S regulatory particles, but several hints have emerged.

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