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Mechanism of Decision Making between Autophagy and Apoptosis Induction upon Endoplasmic Reticulum Stress.
1Department of Molecular Biology, Institute of Biochemistry and Molecular Biology, Semmelweis University, H-1085 Budapest, Hungary.
International Journal of Molecular Sciences
|April 27, 2024
Summary
The unfolded protein response (UPR) uses feedback loops within and between its branches to fine-tune cellular responses to endoplasmic reticulum (ER) stress, impacting cell survival or apoptosis. Understanding these dynamics is crucial for treating ER stress-related diseases.
Area of Science:
- Cell Biology
- Molecular Biology
- Systems Biology
Background:
- The endoplasmic reticulum (ER) dynamically regulates the cellular proteome.
- ER stress, caused by misfolded proteins, activates the unfolded protein response (UPR).
- UPR employs autophagy for damage reduction and apoptosis for excessive stress, with feedback loops governing these outcomes.
Purpose of the Study:
- To review the dynamical characteristics of the ER stress response mechanism.
- To elucidate the role of feedback loops in UPR pathways.
- To highlight the medical importance of understanding ER stress response dynamics.
Main Methods:
- Theoretical modeling of cellular stress responses.
- Molecular biological techniques to study UPR.
- Analysis of feedback loop mechanisms within and between UPR branches.
Main Results:
- Feedback loops operate not only within but also between UPR branches.
- These feedback loops dynamically fine-tune the cellular response to ER stress.
- The interplay of feedback loops dictates the cell's life-and-death decision.
Conclusions:
- Dynamic feedback loops are critical for managing ER stress.
- Understanding these regulatory mechanisms is vital for addressing ER stress-related diseases.
- This review synthesizes current knowledge on UPR dynamics and their control over cellular fate.
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