EMD-0763

Single-particle
16.87 Å
EMD-0763 Deposition: 23/08/2019
Map released: 18/09/2019
Last modified: 09/10/2019
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-0763

TRiC at 0.1 mM ADP-AlFx, Conformation 3, 0.1-C3

EMD-0763

Single-particle
16.87 Å
EMD-0763 Deposition: 23/08/2019
Map released: 18/09/2019
Last modified: 09/10/2019
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Saccharomyces cerevisiae
Sample: TRiC complex

Deposition Authors: Jin ML, Cong Y
An ensemble of cryo-EM structures of TRiC reveal its conformational landscape and subunit specificity.
Jin M, Han W, Liu C, Zang Y, Li J, Wang F, Wang Y, Cong Y
(2019) PNAS , 116 , 19513 - 19522
PUBMED: 31492816
DOI: doi:10.1073/pnas.1903976116
ISSN: 1091-6490
ASTM: PNASA6
Abstract:
TRiC/CCT assists the folding of ∼10% of cytosolic proteins through an ATP-driven conformational cycle and is essential in maintaining protein homeostasis. Here, we determined an ensemble of cryo-electron microscopy (cryo-EM) structures of yeast TRiC at various nucleotide concentrations, with 4 open-state maps resolved at near-atomic resolutions, and a closed-state map at atomic resolution, revealing an extra layer of an unforeseen N-terminal allosteric network. We found that, during TRiC ring closure, the CCT7 subunit moves first, responding to nucleotide binding; CCT4 is the last to bind ATP, serving as an ATP sensor; and CCT8 remains ADP-bound and is hardly involved in the ATPase-cycle in our experimental conditions; overall, yeast TRiC consumes nucleotide in a 2-ring positively coordinated manner. Our results depict a thorough picture of the TRiC conformational landscape and its allosteric transitions from the open to closed states in more structural detail and offer insights into TRiC subunit specificity in ATP consumption and ring closure, and potentially in substrate processing.