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Updated: May 31, 2026
10:56
Assays for the Degradation of Misfolded Proteins in Cells
Published on: August 28, 2016
Cellular strategies of protein quality control
Bryan Chen1, Marco Retzlaff, Thomas Roos
1Department of Biology and BioX Program, Stanford University, Stanford, California 94305, USA.
Cold Spring Harbor Perspectives in Biology
|July 13, 2011
Summary
Eukaryotic cells use protein quality control systems involving chaperones to refold, degrade, or sequester misfolded proteins, maintaining proteome integrity and cell viability. This review explores these strategies and their links to protein misfolding diseases.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Eukaryotic cells constantly face challenges from misfolded proteins that disrupt protein homeostasis and threaten cell survival.
- A complex network of molecular chaperones and protein degradation machinery actively maintains proteome integrity.
- Cellular protein quality control employs three interconnected strategies: refolding, degradation, or sequestration of misfolded proteins.
Purpose of the Study:
- To discuss the spatial and temporal organization of cellular quality control mechanisms.
- To explore the critical role of molecular chaperones in directing the fate of misfolded proteins.
- To examine the implications of these quality control strategies in human diseases associated with protein misfolding and aggregation.
Main Methods:
- Literature review and synthesis of existing research on protein quality control pathways.
- Analysis of the roles of molecular chaperones in protein folding, degradation, and compartmentalization.
- Discussion of the connection between dysregulated protein quality control and human disease pathogenesis.
Main Results:
- Protein quality control involves intricate spatial and temporal regulation of refolding, degradation, and sequestration pathways.
- Molecular chaperones are key determinants of whether a misfolded protein is salvaged or eliminated.
- Disruptions in these quality control mechanisms contribute to the development of various human diseases.
Conclusions:
- The coordinated action of cellular quality control pathways is essential for maintaining proteostasis.
- Understanding the organization and regulation of these pathways provides insights into disease mechanisms.
- Targeting protein quality control represents a potential therapeutic strategy for protein misfolding disorders.
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