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Assays for the Degradation of Misfolded Proteins in Cells
Published on: August 28, 2016
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New MAPS for misfolded proteins.
Norbert Volkmar1, Emma Fenech1, John C Christianson1
1Ludwig Institute for Cancer Research, University of Oxford, Oxford OX2 6TT, UK.
Nature Cell Biology
|June 29, 2016
Summary
Cells possess a backup system for clearing misfolded proteins via secretion, utilizing USP19 when proteasomal degradation fails. This Misfolding-Associated Protein Secretion (MAPS) pathway impacts cellular homeostasis and disease transmission.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cellular homeostasis relies on efficient clearance of misfolded proteins.
- The ubiquitin-proteasome system is the primary pathway for degrading misfolded cytoplasmic proteins.
Discussion:
- A novel Misfolding-Associated Protein Secretion (MAPS) pathway is identified.
- This pathway involves the deubiquitylase USP19.
- MAPS acts as a parallel system to proteasomal degradation for misfolded proteins.
Key Insights:
- USP19 facilitates the secretion of misfolded cytoplasmic proteins.
- MAPS becomes active when proteasomal degradation is compromised.
- This secretion mechanism is crucial for protein quality control.
Outlook:
- MAPS has significant implications for understanding proteinopathies and prion-like diseases.
- Further research into MAPS could reveal new therapeutic targets for diseases involving protein misfolding.
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