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Assays for the Degradation of Misfolded Proteins in Cells
Published on: August 28, 2016
Mitochondrial protein quality control systems in aging and disease
Karin Luce1, Andrea C Weil, Heinz D Osiewacz
1Johann Wolfgang Goethe University, Faculty for Biosciences and Cluster of Excellence Macromolecular Complexes, Institute of Molecular Biosciences, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany.
Advances in Experimental Medicine and Biology
|October 5, 2010
Summary
Cellular protein quality control (PQC) systems maintain protein integrity, preventing aging and disease. Mitochondrial PQC, crucial for cellular health, declines with age and neurodegeneration.
Area of Science:
- Cellular Biology
- Biochemistry
- Molecular Biology
Background:
- Protein integrity is vital for biological systems; damage leads to aging and disease.
- Cells possess hierarchical protein quality control (PQC) pathways to manage misfolded or damaged proteins.
- Reactive oxygen species (ROS) cause molecular damage, particularly to mitochondrial proteins.
Purpose of the Study:
- To summarize current knowledge of cellular quality control systems.
- To emphasize the role of the mitochondrial PQC system.
- To explore the impact of mitochondrial PQC on aging and disease.
Main Methods:
- Review of cellular pathways for detecting, refolding, and degrading proteins.
- Examination of autophagy and apoptosis as cellular damage responses.
- Focus on the components and function of the mitochondrial PQC system, including chaperones and proteases.
Main Results:
- Mitochondria have a robust PQC system involving chaperones and proteases.
- Impairment of mitochondrial PQC components, like Lon protease, occurs during aging and neurodegenerative diseases.
- Functional decline in PQC contributes to cellular damage and disease progression.
Conclusions:
- Cellular PQC is essential for preventing degenerative processes.
- The mitochondrial PQC system is critical for maintaining cellular function and health.
- Dysfunctional mitochondrial PQC is implicated in aging and neurodegenerative diseases.
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