5VHO

Conformational Landscape of the p28-Bound Human Proteasome Regulatory Particle

Summary for 5VHO

• Entry DOI: 10.2210/pdb5vho/pdb
• Related: 5VGZ 5VHF 5VHH 5VHI 5VHJ 5VHM 5VHN 5VHP 5VHQ 5VHR 5VHS
• EMDB information: 8672 8674 8675 8676 8677 8678 8679 8680 8681 8682 8683 8684
• Descriptor: 26S proteasome non-ATPase regulatory subunit 10, 26S proteasome regulatory subunit 7, 26S proteasome regulatory subunit 4, ... (8 entities in total)
• Functional Keywords: p28, 26s proteasome, regulatory particle, 19s, gankyrin, hydrolase
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 8
• Total formula weight: 295960.10

Authors

Lu, Y.,Wu, J.,Dong, Y.,Chen, S.,Sun, S.,Ma, Y.B.,Ouyang, Q.,Finley, D.,Kirschner, M.W.,Mao, Y. (deposition date: 2017-04-13, release date: 2017-08-23, Last modification date: 2024-03-13)

Primary citation

Lu, Y.,Wu, J.,Dong, Y.,Chen, S.,Sun, S.,Ma, Y.B.,Ouyang, Q.,Finley, D.,Kirschner, M.W.,Mao, Y.
Conformational Landscape of the p28-Bound Human Proteasome Regulatory Particle.
Mol. Cell, 67:322-333.e6, 2017

PubMed Abstract: The proteasome holoenzyme is activated by its regulatory particle (RP) consisting of two subcomplexes, the lid and the base. A key event in base assembly is the formation of a heterohexameric ring of AAA-ATPases, which is guided by at least four RP assembly chaperones in mammals: PAAF1, p28/gankyrin, p27/PSMD9, and S5b. Using cryogenic electron microscopy, we analyzed the non-AAA structure of the p28-bound human RP at 4.5 Å resolution and determined seven distinct conformations of the Rpn1-p28-AAA subcomplex within the p28-bound RP at subnanometer resolutions. Remarkably, the p28-bound AAA ring does not form a channel in the free RP and spontaneously samples multiple "open" and "closed" topologies at the Rpt2-Rpt6 and Rpt3-Rpt4 interfaces. Our analysis suggests that p28 assists the proteolytic core particle to select a specific conformation of the ATPase ring for RP engagement and is released in a shoehorn-like fashion in the last step of the chaperone-mediated proteasome assembly.

PubMed: 28689658
DOI: 10.1016/j.molcel.2017.06.007

Experimental method

ELECTRON MICROSCOPY (8.3 Å)