Hsp90 oligomerization process: How can p23 drive the chaperone machineries?
Eléonore Lepvrier1, Michaël Nigen2, Laura Moullintraffort1
1Translation and Folding, UMR-CNRS 6290, Université de Rennes 1, Campus Beaulieu, 35042 Rennes Cedex, France.
Biochimica Et Biophysica Acta
|July 8, 2015
Summary
The heat shock protein 90 (Hsp90) interacts with p23, influencing its self-association. This study reveals p23 acts as a "protein wedge," modulating Hsp90 dimer closure and oligomerization.
Area of Science:
- Molecular Biology
- Protein Dynamics
- Biochemistry
Background:
- Heat shock protein 90 (Hsp90) is a flexible dimer known to self-associate.
- Previous research characterized Mg2+-induced Hsp90 oligomerization.
Purpose of the Study:
- To investigate the interaction between p23 and Hsp90 dimers and oligomers.
- To elucidate the role of p23 in Hsp90 oligomerization dynamics.
Main Methods:
- Analytical ultracentrifugation
- Size-exclusion chromatography coupled to multi-angle laser light scattering
- High-mass matrix-assisted laser desorption/ionization time-of-flight mass spectrometry
Main Results:
- p23 binds predominantly to the Hsp90 dimer but also interacts with Hsp90 oligomers.
- p23 shifts the Hsp90 dimer-oligomer equilibrium towards the dimer state.
- Hsp90:p23 binding stoichiometry decreases as Hsp90 oligomerization increases.
Conclusions:
- p23 acts as a "protein wedge" in Hsp90 dimer closure and oligomerization.
- p23 plays a regulatory role in Hsp90 conformational dynamics and self-association.
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