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Updated: Jun 26, 2026

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
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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
PubMed

Insights

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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