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Updated: Jul 9, 2026
07:35
Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
Mechanisms of mitochondrial outer membrane permeabilization.
Dominic James1, Philippe A Parone, Olivier Terradillos
1Department of Cell Biology, University of Geneva, Quai Ernest-Ansermet 30, Geneva, Switzerland.
Novartis Foundation Symposium
|December 14, 2007
Summary
Pro-apoptotic Bcl-2 proteins like Bax and Bak trigger mitochondrial outer membrane permeabilization (MOMP), releasing proteins such as cytochrome c. The exact mechanisms of protein oligomerization and MOMP, and the role of mitochondrial fission, are still under investigation.
Area of Science:
- Cell biology
- Molecular biology
- Biochemistry
Background:
- Apoptotic stimuli activate pro-apoptotic Bcl-2 family members, including Bax and Bak.
- Activation leads to oligomerization and mitochondrial outer membrane permeabilization (MOMP).
- MOMP results in the release of inter-membrane space proteins like cytochrome c and Smac/DIABLO.
Purpose of the Study:
- To elucidate the mechanisms of pro-apoptotic Bcl-2 member oligomerization.
- To understand the molecular events leading to MOMP.
- To investigate the role of mitochondrial fission in apoptosis.
Main Methods:
- The study focuses on the molecular mechanisms of apoptosis.
- It examines the role of Bcl-2 family proteins in mitochondrial membrane permeabilization.
- Investigates the process of mitochondrial fission in the context of MOMP.
Main Results:
- Pro-apoptotic Bcl-2 proteins oligomerize upon apoptotic stimuli.
- Oligomerization leads to MOMP and release of mitochondrial proteins.
- Mitochondrial network fragmentation is observed during MOMP.
Conclusions:
- Bcl-2 family proteins play a crucial role in initiating MOMP.
- The precise mechanisms driving oligomerization and MOMP require further investigation.
- The involvement of mitochondrial fission in these apoptotic events remains unclear.
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