Structure of the Blm10-20 S proteasome complex by cryo-electron microscopy. Insights into the mechanism of activation of mature yeast proteasomes.

ABSTRACT: The 20 S proteasome is regulated at multiple levels including association with endogenous activators. Two activators have been described for the yeast 20 S proteasome: the 19 S regulatory particle and the Blm10 protein. The sequence of Blm10 is 20% identical to the mammalian PA200 protein. Recent studies have shown that the sequences of Blm10 and PA200 each contain multiple HEAT-repeats and that each binds to the ends of mature proteasomes, suggesting a common structural and biochemical function. In order to advance structural studies, we have developed an efficient purification method that produces high yields of stoichiometric Blm10-mature yeast 20 S proteasome complexes and we constructed a three-dimensional (3D) model of the Blm10-20 S complex from cryo-electron microscopy images. This

SUBMITTER: Iwanczyk J 

PROVIDER: S-EPMC2980845 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature