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Published on: February 12, 2019
GroEL stimulates protein folding through forced unfolding
Zong Lin1, Damian Madan, Hays S Rye
1Department of Molecular Biology, Princeton University, Schultz Laboratory, Princeton, New Jersey 08544, USA.
Nature Structural & Molecular Biology
|March 4, 2008
Summary
Chaperonins like GroEL assist protein folding. This study shows that GroEL actively unfolds substrate proteins, which surprisingly enhances their ability to fold correctly into their native states.
Area of Science:
- Biochemistry
- Molecular Biology
- Protein Folding
Background:
- Many proteins require molecular chaperones, such as the GroEL-GroES chaperonin system, for proper folding.
- The precise mechanism by which these chaperonins facilitate protein folding is not fully understood.
Purpose of the Study:
- To investigate the role of GroEL-mediated unfolding in the protein folding process.
- To elucidate the mechanism by which the GroEL-GroES complex assists non-native proteins.
Main Methods:
- Studied substrate protein capture and conformational changes within the GroEL-ADP-GroES complex.
- Analyzed the effect of ATP binding on substrate protein unfolding and subsequent folding.
Main Results:
- Substrate proteins are captured in a compact state by the GroEL-ADP-GroES complex.
- ATP binding induces rapid, forced unfolding of the captured substrate protein.
- The extent of substrate protein unfolding is directly proportional to its successful folding after release.
Conclusions:
- Forced unfolding by GroEL is a critical mechanism that enhances protein folding.
- GroEL employs a multifaceted strategy, including unfolding, to promote the correct folding of substrate proteins.
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