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Updated: Jun 26, 2026
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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
Dynamics of outer mitochondrial membrane permeabilization during apoptosis
M Rehm1, H J Huber, C T Hellwig
1Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland. mrehm@rcsi.ie
Cell Death and Differentiation
|January 13, 2009
Summary
Sibling cells undergo programmed cell death together, revealing new insights into mitochondrial outer membrane permeabilization (MOMP) dynamics during apoptosis. This synchronized cell death allows for high-resolution imaging of MOMP.
Area of Science:
- Cell Biology
- Biophysics
Background:
- Apoptosis, or programmed cell death, is a fundamental biological process.
- Individual cells initiate apoptosis at seemingly random times.
- Mitochondrial outer membrane permeabilization (MOMP) is a critical and rapid event in apoptosis.
Purpose of the Study:
- To investigate the dynamics of MOMP at unprecedented temporal resolution.
- To analyze clonal cell-to-cell variability in apoptosis execution.
- To elucidate the mechanisms underlying MOMP propagation.
Main Methods:
- High-speed cellular imaging of synchronized sibling HeLa cell pairs.
- Analysis of cytochrome-c-GFP redistribution kinetics.
- Computational modeling using partial differential equations.
- Pharmacological inhibition of protein kinase CK2.
Main Results:
- Sibling cells exhibit synchronous apoptosis, enabling high-resolution MOMP studies.
- Determined kinetics of pore formation during MOMP, differentiating responses to intrinsic and extrinsic apoptotic stimuli.
- Observed MOMP spreading as a wave, with reduced frequency upon protein kinase CK2 inhibition.
- Computational models support diffusion-adsorption mechanisms for MOMP signal propagation.
Conclusions:
- Synchronized apoptosis in sibling cells provides a novel system for studying MOMP.
- The study offers detailed mechanistic insights into MOMP dynamics and propagation.
- Identified protein kinase CK2 as a modulator of MOMP wave frequency.
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