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Updated: May 11, 2026
06:06
In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
Deadly encounter: ubiquitin meets apoptosis
Veronika Jesenberger1, Stefan Jentsch
1Department of Molecular Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18 a, 82152 Martinsried, Germany. Jesenber@biochem.mpg.de
Nature Reviews. Molecular Cell Biology
|February 12, 2002
Summary
The ubiquitin/proteasome pathway degrades intracellular proteins, crucial for cell processes and apoptosis regulation. This pathway targets cell death molecules and inactivates death executors.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- The ubiquitin/proteasome pathway is the primary non-lysosomal mechanism for intracellular protein degradation in eukaryotic cells.
- This pathway plays essential roles in fundamental cellular processes including cell-cycle progression, gene transcription, and antigen processing.
Purpose of the Study:
- To elucidate the role of the ubiquitin/proteasome pathway in the regulation of apoptosis (programmed cell death).
- To identify regulatory molecules involved in programmed cell death as substrates of the proteasome.
- To investigate the involvement of apoptosis regulators in the proteolytic inactivation of death executors.
Main Methods:
- Analysis of protein degradation pathways.
- Identification of proteasome substrates.
- Investigation of molecular interactions between apoptosis regulators and the proteasome.
Main Results:
- Regulatory molecules critical for programmed cell death have been identified as substrates targeted for degradation by the proteasome.
- Key regulators of apoptosis actively participate in the proteolytic inactivation of molecules that execute cell death.
Conclusions:
- The ubiquitin/proteasome pathway is pivotal in regulating apoptosis.
- The pathway controls programmed cell death by degrading regulatory molecules and inactivating death executors.
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Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
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