English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Late events in the assembly of 20S proteasomes

MPS-Authors
There are no MPG-Authors available
Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Mayr, U., Seemüller, E., Müller, S. A., Engel, A., & Baumeister, W. (1998). Late events in the assembly of 20S proteasomes. Journal of Structural Biology, 124(2-3), 179-188.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0010-7248-B
Abstract
Electron microscopy and STEM mass measurements have been used to characterize late intermediates in the assembly pathway of wildtype and mutant Rhodococcus proteasomes. A proteolytically inactive and processing-incompetent mutant, beta K33A, allowed a short-lived late intermediate of the pathway to be captured, the preholoproteasome. In this fully assembled 20S complex the 14 propeptides with an aggregate mass of 100 kDa fill the whole central cavity and most of the two antechambers. It is further shown that in wildtype Rhodococcus proteasomes the propeptides are degraded in a processive manner undergoing multiple cleavages before the products are discharged and the inner cavities are cleared. It appears that the docking of two half-proteasomes, i.e., preholoproteasome formation, is sufficient to trigger autocleavage of the Gly-1/Thr1 bond necessary for active site formation and the subsequent degradation of the propeptides. (C) 1998 Academic Press. [References: 33]