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Assays for the Degradation of Misfolded Proteins in Cells
Published on: August 28, 2016
Protein misfolding and cellular stress: an overview
Methods in Molecular Biology (Clifton, N.J.)
|August 12, 2010
Summary
Cellular protein quality control and unfolded protein responses maintain protein function. Misfolded proteins trigger oxidative stress, impacting mitochondrial dynamics and leading to a cycle of cellular damage.
Area of Science:
- Cellular Biology
- Biochemistry
- Molecular Medicine
Background:
- Cellular survival and death are critical processes, with imbalances contributing to diseases like cancer and tissue degeneration.
- Protein homeostasis is maintained by protein quality control (PQC) systems and unfolded protein responses (UPRs).
- Misfolded proteins can disrupt cellular functions and lead to oxidative stress.
Purpose of the Study:
- To elucidate cellular survival mechanisms, focusing on protein quality control and unfolded protein responses.
- To describe how misfolded proteins generate oxidative stress via reactive oxygen and nitrogen species.
- To examine the effects of oxidative stress on mitochondrial dynamics and cellular cleaning systems, and the resulting protein damage.
Main Methods:
- Review of cellular survival mechanisms including protein quality control (PQC) systems (molecular chaperones, intracellular proteases).
- Analysis of unfolded protein responses (UPRs) and their role in antioxidant system induction.
- Investigation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) generation, particularly from mitochondrial sources.
- Examination of oxidative stress effects on mitochondrial dynamics (fission, fusion) and mitophagy/mitoptosis.
Main Results:
- PQC systems and UPRs are crucial for maintaining protein folding and function across cellular compartments.
- Misfolded proteins induce oxidative stress through ROS and RNS, originating from mitochondrial respiration and mtNOS.
- Oxidative stress impacts mitochondrial dynamics and mitophagy, creating a feedback loop with protein misfolding.
Conclusions:
- Cellular survival is tightly regulated by PQC and UPRs to prevent disease.
- Misfolded proteins initiate a cascade involving oxidative stress and mitochondrial dysfunction.
- Understanding these interconnected pathways is key to addressing diseases linked to protein misfolding and oxidative damage.
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