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Published on: April 1, 2011
The mitochondrial membrane potential (deltapsi(m)) in apoptosis; an update
1Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Building 13D, Melbourne 3800, Australia.
Summary
Mitochondrial dysfunction and apoptosis involve changes in mitochondrial membrane potential (Δψm). The timing of Δψm dissipation varies, impacting apoptosis signaling and factor release, potentially due to measurement methods.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Mitochondrial dysfunction is implicated in apoptosis induction.
- Opening of the mitochondrial permeability transition pore leads to key apoptotic events.
- The role of transmembrane potential (Δψm) in apoptosis is debated.
Purpose of the Study:
- To review the conflicting data on the role of Δψm in apoptosis.
- To investigate whether Δψm loss is an early or late event in apoptosis.
- To explore factors contributing to discrepancies in Δψm research.
Main Methods:
- Review of existing literature on apoptosis and mitochondrial function.
- Analysis of studies investigating Δψm changes during apoptosis.
- Examination of factors affecting Δψm measurements.
Main Results:
- Loss of Δψm can be an early or late event in apoptosis, depending on the system and stimulus.
- Δψm loss is not always required for cytochrome c release but is for AIF release.
- Discrepancies may arise from the sensitivity and accuracy of fluorochromes used to measure Δψm.
Conclusions:
- The timing of Δψm dissipation in apoptosis is context-dependent.
- Accurate measurement of Δψm is crucial for understanding its role in apoptosis.
- Further research is needed to reconcile conflicting findings regarding Δψm and apoptosis.
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