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Insights into the molecular architecture of the 26S proteasome.

ABSTRACT: Cryo-electron microscopy in conjunction with advanced image analysis was used to analyze the structure of the 26S proteasome and to elucidate its variable features. We have been able to outline the boundaries of the ATPase module in the "base" part of the regulatory complex that can vary in its position and orientation relative to the 20S core particle. This variation is consistent with the "wobbling" model that was previously proposed to explain the role of the regulatory complex in opening the gate in the alpha-rings of the core particle. In addition, a variable mass near the mouth of the ATPase ring has been identified as Rpn10, a multiubiquitin receptor, by correlating the electron microscopy data with quantitative mass spectrometry.

SUBMITTER: Nickell S

PROVIDER: S-EPMC2715492 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Insights into the molecular architecture of the 26S proteasome.

Nickell Stephan S Beck Florian F Scheres Sjors H W SH Korinek Andreas A Förster Friedrich F Lasker Keren K Mihalache Oana O Sun Na N Nagy István I Sali Andrej A Plitzko Jürgen M JM Carazo Jose-Maria JM Mann Matthias M Baumeister Wolfgang W

Proceedings of the National Academy of Sciences of the United States of America 20090706 29

Cryo-electron microscopy in conjunction with advanced image analysis was used to analyze the structure of the 26S proteasome and to elucidate its variable features. We have been able to outline the boundaries of the ATPase module in the "base" part of the regulatory complex that can vary in its position and orientation relative to the 20S core particle. This variation is consistent with the "wobbling" model that was previously proposed to explain the role of the regulatory complex in opening the ...[more]

PMID: 19581588

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