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Updated: Jun 10, 2026
09:25
Quantifying Subcellular Ubiquitin-proteasome Activity in the Rodent Brain
Published on: May 21, 2019
Ubiquitin-proteasome system and mitochondria - reciprocity
Nurit Livnat-Levanon1, Michael H Glickman
1Department of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
Biochimica Et Biophysica Acta
|August 3, 2010
Summary
The ubiquitin-proteasome system (UPS) recycles mitochondrial proteins and regulates mitochondrial morphology and function. Mitochondria-generated reactive oxygen species (ROS) also impact UPS activity, revealing a reciprocal relationship.
Area of Science:
- Cell Biology
- Biochemistry
- Mitochondrial Biology
Background:
- Mitochondria and the ubiquitin-proteasome system (UPS) interact for cellular protein turnover.
- Mitochondrial outer membrane proteins like Fzo1 are ubiquitinated and degraded by the UPS.
- UPS components are implicated in mitochondrial morphology and respiration.
Purpose of the Study:
- To review the regulation of mitochondrial morphology and metabolic function by the UPS.
- To explore the reciprocal relationship between mitochondrial reactive oxygen species (ROS) and UPS activity.
Main Methods:
- Literature review of studies linking UPS components to mitochondrial function.
- Analysis of ubiquitination and proteasomal degradation of mitochondrial proteins.
- Examination of the impact of ROS on UPS components.
Main Results:
- The UPS plays a role in recycling mitochondrial proteins, particularly at the outer membrane.
- Ubiquitination targets damaged mitochondria for autophagic degradation.
- Mitochondrial ROS generation affects UPS component sensitivity and activity.
Conclusions:
- The UPS is crucial for mitochondrial quality control and function.
- A bidirectional relationship exists between mitochondria and the UPS, influenced by ROS.
- Understanding this interplay is vital for cellular health and disease.
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