Where killers meet--permeabilization of the outer mitochondrial membrane during apoptosis

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Updated: May 15, 2026

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
09:27

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue

Published on: March 23, 2015

Tom Bender1, Jean-Claude Martinou

  • 1Department of Cell Biology, University of Geneva, 1211 Geneva 4, Switzerland.

Cold Spring Harbor Perspectives in Biology
|January 4, 2013
PubMed

Insights

Mitochondria, often life supporters, also drive cellular death via mitochondrial outer membrane permeabilization (MOMP). Bcl-2 family proteins control MOMP by regulating Bax and Bak pore formation, releasing cell death factors.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Mitochondria play a dual role in cellular life and death.
  • Mitochondrial outer membrane permeabilization (MOMP) is a key step in apoptosis.
  • The Bcl-2 protein family regulates MOMP.

Purpose of the Study:

  • To elucidate the mechanisms controlling MOMP.
  • To detail the role of Bcl-2 family interactions in Bax and Bak activation.
  • To highlight the step-by-step process of Bax/Bak pore formation.

Main Methods:

  • Literature review and synthesis of current research on MOMP.
  • Analysis of protein-protein interactions within the Bcl-2 family.
  • Examination of the role of mitochondrial components in MOMP.

Main Results:

  • Bcl-2 family members' interactions dictate Bax and Bak activation and oligomerization.
  • Specific sequence of events leading to MOMP, including Bax/Bak pore formation, is detailed.
  • Mitochondrial proteins and lipids are integral to MOMP regulation.

Conclusions:

  • MOMP is a tightly regulated process involving Bcl-2 family proteins and mitochondrial components.
  • Understanding MOMP mechanisms is crucial for studying apoptosis and cell death pathways.

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