Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz

Logo MUG-Forschungsportal

Gewählte Publikation:

SHR Neuro Krebs Kardio Lipid

Zierer, BK; Rübbelke, M; Tippel, F; Madl, T; Schopf, FH; Rutz, DA; Richter, K; Sattler, M; Buchner, J.
Importance of cycle timing for the function of the molecular chaperone Hsp90.
NAT STRUCT MOL BIOL. 2016; 23(11): 1020-1028.
Web of Science PubMed FullText FullText_MUG

 

Autor/innen der Med Uni Graz:
Madl Tobias
Gendermonitor:
Altmetrics:

Abstract:
Hsp90 couples ATP hydrolysis to large conformational changes essential for activation of client proteins. The structural transitions involve dimerization of the N-terminal domains and formation of 'closed states' involving the N-terminal and middle domains. Here, we used Hsp90 mutants that modulate ATPase activity and biological function as probes to address the importance of conformational cycling for Hsp90 activity. We found no correlation between the speed of ATP turnover and the in vivo activity of Hsp90: some mutants with almost normal ATPase activity were lethal, and some mutants with lower or undetectable ATPase activity were viable. Our analysis showed that it is crucial for Hsp90 to attain and spend time in certain conformational states: a certain dwell time in open states is required for optimal processing of client proteins, whereas a prolonged population of closed states has negative effects. Thus, the timing of conformational transitions is crucial for Hsp90 function and not cycle speed.

© Meduni Graz Impressum