TCB Publications - Abstract

Marc Wehmer, Till Rudack, Florian Beck, Antje Aufderheide, Günter Pfeifer, Jürgen M. Plitzko, Friedrich Förster, Klaus Schulten, Wolfgang Baumeister, and Eri Sakata. Structural insights into the functional cycle of the ATPase module of the 26S proteasome. Proceedings of the National Academy of Sciences, USA, 114:1305-1310, 2017.

WEHM2017 In eukaryotic cells, the ubiquitin/proteasome system (UPS) is responsible for the regulated degradation of intracellular proteins. The 26S holocomplex comprises the core particle (CP), where proteolysis takes place, and one or two regulatory particles (RPs). The base of the RP is formed by a heterohexameric AAA+ ATPase module, which unfolds and translocates substrates into the CP. Applying single-particle cryo-electron microscopy (cryo-EM) and image classification to samples in the presence of different nucleotides and nucleotide analogs, we were able to observe four distinct conformational states (s1 to s4). The resolution of the four conformers allowed for the construction of atomic models of the AAA+ ATPase module as it progresses through the functional cycle. In a hitherto unobserved state (s4), the gate controlling access to the CP is open. The structures described in this study allow us to put forward a model for the 26S functional cycle driven by ATP hydrolysis.

Download Full Text

The manuscripts available on our site are provided for your personal use only and may not be retransmitted or redistributed without written permissions from the paper's publisher and author. You may not upload any of this site's material to any public server, on-line service, network, or bulletin board without prior written permission from the publisher and author. You may not make copies for any commercial purpose. Reproduction or storage of materials retrieved from this web site is subject to the U.S. Copyright Act of 1976, Title 17 U.S.C.

Download full text: PDF ( 1.9MB), Journal