Cooperation of local motions in the Hsp90 molecular chaperone ATPase mechanism

Schulze, Andrea, Beliu, Gerti, Helmerich, Dominic A, Schubert, Jonathan, Pearl, Laurence H, Prodromou, Chrisostomos and Neuweiler, Hannes (2016) Cooperation of local motions in the Hsp90 molecular chaperone ATPase mechanism. Nature Chemical Biology, 12 (8). pp. 628-635. ISSN 1552-4450

[img] PDF - Accepted Version
Download (1MB)

Abstract

The Hsp90 chaperone is a central node of protein homeostasis activating a large number of diverse client proteins. Hsp90 functions as a molecular clamp that closes and opens in response to the binding and hydrolysis of ATP. Crystallographic studies define distinct conformational states of the mechanistic core implying structural changes that have not yet been observed in solution. Here, we engineered one-nanometer fluorescence probes based on photo-induced electron transfer into yeast Hsp90 to observe these motions. We found that the ATPase activity of the chaperone was reflected in the kinetics of specific structural rearrangements at remote positions that acted cooperatively. Nanosecond single-molecule fluorescence fluctuation analysis uncovered that critical structural elements that undergo rearrangement are mobile on a sub-millisecond time scale. We identified a two-step mechanism for lid closure over the nucleotide-binding pocket. The activating co-chaperone Aha1 mobilizes the lid of apo Hsp90, suggesting an early role in the catalytic cycle.

Item Type: Article
Schools and Departments: School of Life Sciences > Biochemistry
Subjects: Q Science > QH Natural history > QH0301 Biology > QH0324 Methods of research. Technique. Experimental biology
Depositing User: Chrisostomos Prodromou
Date Deposited: 04 May 2017 14:20
Last Modified: 04 May 2017 14:22
URI: http://sro.sussex.ac.uk/id/eprint/67665

View download statistics for this item

📧 Request an update