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Published on: March 26, 2014
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Systematic identification of 20S proteasome substrates.
Monika Pepelnjak1, Rivkah Rogawski2, Galina Arkind2
1Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, Zurich, Switzerland.
Molecular Systems Biology
|January 29, 2024
Summary
The 20S proteasome independently degrades hundreds of proteins, including RNA/DNA-binding proteins. This pathway is crucial for cellular regulation and is affected by oxidative stress.
Area of Science:
- Cell Biology
- Biochemistry
- Proteomics
Background:
- Proteasomal degradation was historically linked solely to the ubiquitin-26S proteasome pathway.
- The core 20S proteasome is now recognized as an independent degradation machine, comprising about half of cellular proteasomes.
Purpose of the Study:
- To comprehensively identify substrates targeted by the 20S proteasome.
- To investigate the characteristics and regulation of 20S proteasome substrates.
Main Methods:
- Advanced mass spectrometry
- Biochemical analyses
- Cellular analyses
Main Results:
- Hundreds of 20S proteasome substrates were identified.
- Substrates included RNA/DNA-binding proteins with intrinsically disordered regions, often nuclear.
- Oxidative stress reduced proteasome activity and increased substrate disorder.
Conclusions:
- The 20S proteasome plays a significant role in protein degradation beyond the 26S pathway.
- 20S proteasome substrates possess distinct characteristics and are involved in cellular regulation.
- Proteasome oxidation impacts substrate degradation, particularly under stress conditions.
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