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Updated: Sep 1, 2025
09:57
Examining Proteasome Assembly with Recombinant Archaeal Proteasomes and Nondenaturing PAGE: The Case for a Combined Approach
Published on: December 17, 2016
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DUB-le vision: snapshots of the proteasome during substrate processing
Helena M Schnell1, John Hanna1
1Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
Trends in Biochemical Sciences
|August 13, 2022
Summary
The proteasome recycles ubiquitin signals using deubiquitinating enzymes (DUBs). New research shows how Usp14, a key DUB, interacts with and is controlled by the proteasome.
Area of Science:
- Biochemistry
- Molecular Biology
- Cellular Biology
Background:
- Ubiquitin modification targets proteins for proteasomal degradation.
- The ubiquitin tag is recycled after protein destruction.
- Proteasomes possess three distinct deubiquitinating enzymes (DUBs).
Purpose of the Study:
- To investigate the regulatory role of Usp14 in proteasome function.
- To understand how the proteasome controls Usp14 activity.
Main Methods:
- Biochemical assays to study enzyme activity.
- Proteasome complex analysis.
- Ubiquitin-conjugation and deconjugation experiments.
Main Results:
- Usp14 directly interacts with the proteasome.
- Proteasome association modulates Usp14's deubiquitinating activity.
- Usp14's function is integrated with the proteasome's degradation cycle.
Conclusions:
- Usp14 is a crucial regulator of proteasomal degradation.
- The proteasome actively controls its associated DUBs, including Usp14.
- This interplay ensures efficient protein turnover and ubiquitin recycling.
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