A molecular mechanism of chaperone-client recognition
Lichun He1, Timothy Sharpe1, Adam Mazur1
1Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland.
Science Advances
|February 1, 2017
Summary
Molecular chaperones like Spy help proteins fold correctly. This study reveals Spy recognizes and stabilizes unfolded proteins by targeting flexible regions, aiding cellular protein homeostasis.
Area of Science:
- Protein folding and molecular chaperones
- Biophysics and structural biology
Background:
- Molecular chaperones maintain protein homeostasis but their atomic-level mechanisms are unclear.
- Understanding chaperone-client interactions is crucial for protein folding research.
Purpose of the Study:
- To elucidate the atomic-level mechanism of client recognition by the ATP-independent chaperone Spy.
- To derive a structural model of the chaperone-client complex.
Main Methods:
- Nuclear magnetic resonance (NMR) spectroscopy was employed.
- Analysis focused on the interaction between Spy and its client Im7.
Main Results:
- Spy selectively recognizes flexible, locally frustrated regions of partially folded client Im7 dynamically.
- Spy interaction destabilizes partially folded clients but compacts unfolded ones.
- The chaperone enhances client backbone dynamics, facilitating native structure search.
Conclusions:
- Spy's recognition of frustrated segments is a fundamental chaperone mechanism.
- This mechanism aids in achieving cellular protein homeostasis.
- Spy's action promotes efficient protein folding pathways.
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