Redox-regulated chaperones in cell stress responses
1Institute of Biochemistry, Cellular Biochemistry, University of Cologne, Zuelpicher Str. 47a, 50674 Cologne, Germany.
Biochemical Society Transactions
|May 4, 2023
Summary
Cells use redox-regulated chaperones as a first defense against oxidative stress, with cysteine switches controlling their activity to maintain protein homeostasis (proteostasis) during recovery.
Area of Science:
- Cellular Biology
- Biochemistry
- Oxidative Stress Response
Background:
- Proteostasis and redox homeostasis are intrinsically linked.
- Protein quality control pathways are regulated by redox state, enabling rapid cellular responses to oxidative stress.
Purpose of the Study:
- To review the mechanisms of redox-regulated chaperones.
- To elucidate their role in cellular stress responses and proteostasis maintenance.
Main Methods:
- Review of existing literature on redox regulation and chaperone function.
- Analysis of conserved cysteine residues as redox-sensitive switches.
- Examination of interactions between ATP-independent and ATP-dependent chaperone systems.
Main Results:
- ATP-independent chaperones act as an initial defense against protein unfolding and aggregation under oxidative stress.
- Reversible oxidation of cysteine residues triggers conformational changes and activates chaperone complexes.
- Redox-regulated chaperones collaborate with ATP-dependent systems for efficient client refolding and proteostasis recovery.
Conclusions:
- Redox-regulated chaperones are crucial for orchestrating cellular defense against oxidative stress.
- Their stress-specific activation and inactivation are key to restoring proteostasis.
- Understanding these mechanisms is vital for comprehending cellular resilience.
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