PAC1 gene knockout reveals an essential role of chaperone-mediated 20S proteasome biogenesis and latent 20S proteasomes in cellular homeostasis.

ABSTRACT: The 26S proteasome, a central enzyme for ubiquitin-dependent proteolysis, is a highly complex structure comprising 33 distinct subunits. Recent studies have revealed multiple dedicated chaperones involved in proteasome assembly both in yeast and in mammals. However, none of these chaperones is essential for yeast viability. PAC1 is a mammalian proteasome assembly chaperone that plays a role in the initial assembly of the 20S proteasome, the catalytic core of the 26S proteasome, but does not cause a complete loss of the 20S proteasome when knocked down. Thus, both chaperone-dependent and -independent assembly pathways exist in cells, but the contribution of the chaperone-dependent pathway remains unclear. To elucidate its biological significance in mammals, we generated PAC1 conditional kno

SUBMITTER: Sasaki K 

PROVIDER: S-EPMC2916404 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature