5U4P

Protein-protein complex between 26S proteasome regulatory subunit RPN8, RPN11, and Ubiquitin S31

Summary for 5U4P

• Entry DOI: 10.2210/pdb5u4p/pdb
• Descriptor: 26S proteasome regulatory subunit RPN8, 26S proteasome regulatory subunit RPN11, Ubiquitin-40S ribosomal protein S31, ... (5 entities in total)
• Functional Keywords: complex, ubiquitin, proteasome, protein binding
• Biological source: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); More
• Total number of polymer chains: 3
• Total formula weight: 53250.16

Authors

Worden, E.J.,Dong, K.C.,Martin, A. (deposition date: 2016-12-05, release date: 2017-09-06, Last modification date: 2023-10-04)

Primary citation

Worden, E.J.,Dong, K.C.,Martin, A.
An AAA Motor-Driven Mechanical Switch in Rpn11 Controls Deubiquitination at the 26S Proteasome.
Mol. Cell, 67:799-811.e8, 2017

PubMed Abstract: Poly-ubiquitin chains direct protein substrates to the 26S proteasome, where they are removed by the deubiquitinase Rpn11 during ATP-dependent substrate degradation. Rapid deubiquitination is required for efficient degradation but must be restricted to committed substrates that are engaged with the ATPase motor to prevent premature ubiquitin chain removal and substrate escape. Here we reveal the ubiquitin-bound structure of Rpn11 from S. cerevisiae and the mechanisms for mechanochemical coupling of substrate degradation and deubiquitination. Ubiquitin binding induces a conformational switch of Rpn11's Insert-1 loop from an inactive closed state to an active β hairpin. This switch is rate-limiting for deubiquitination and strongly accelerated by mechanical substrate translocation into the AAA+ motor. Deubiquitination by Rpn11 and ubiquitin unfolding by the ATPases are in direct competition. The AAA+ motor-driven acceleration of Rpn11 is therefore important to ensure that poly-ubiquitin chains are removed only from committed substrates and fast enough to prevent their co-degradation.

PubMed: 28844860
DOI: 10.1016/j.molcel.2017.07.023

Experimental method

X-RAY DIFFRACTION (2.5 Å)