How do Chaperones Bind (Partly) Unfolded Client Proteins?
Iva Sučec1, Beate Bersch1, Paul Schanda1,2
1CEA, CNRS, Institut de Biologie Structurale (IBS), Univ. Grenoble Alpes, Grenoble, France.
Frontiers in Molecular Biosciences
|November 11, 2021
Summary
Molecular chaperones utilize dynamic disorder to interact with diverse client proteins, balancing broad interactions with specific client recognition. This review explores atomic-level insights into these dynamic chaperone-client complexes.
Area of Science:
- Cellular Biology
- Biochemistry
- Structural Biology
Background:
- Molecular chaperones maintain cellular protein homeostasis.
- Dynamic disorder in chaperone-client complexes facilitates protein folding and transfer.
- Chaperones interact with clients based on sequence properties, not just 3D structure, leading to promiscuity.
Purpose of the Study:
- To review atomic-level descriptions of chaperone-client complexes.
- To understand the balance between chaperone promiscuity and client specificity.
- To focus on ATP-independent chaperone-client interactions.
Main Methods:
- Review of recent atomic-level structural studies.
- Analysis of chaperone complexes with intrinsically disordered proteins, membrane-protein precursors, and partially folded clients.
- Focus on interactions independent of ATP.
Main Results:
- Dynamic disorder is a crucial feature of chaperone-client complexes.
- Chaperone-client interactions involve multiple types of interactions, including non-hydrophobic ones.
- Chaperones exhibit promiscuity in client binding, influenced by physico-chemical sequence properties.
Conclusions:
- Dynamics play a critical role in the function and specificity of chaperone-client interactions.
- Understanding the factors governing the balance between promiscuity and specificity is essential.
- ATP-independent interactions highlight diverse mechanisms in chaperone-mediated protein folding.
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