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Breaking the mitochondrial barrier

J C Martinou1, D R Green

  • 1Departement de Biologie Cellulaire, Sciences III, 30 quai Ernest Ansermet, 1211 Genève 4, Switzerland. Jean-Claude.Martinou@cellbio.unige.ch.

Nature Reviews. Molecular Cell Biology
|June 20, 2001
PubMed

Insights

Members of the Bcl-2 family regulate mitochondrial outer membrane permeability. We propose these proteins form pores autonomously, rather than interacting with the permeability transition pore complex.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The Bcl-2 family comprises key regulators of apoptosis.
  • These proteins control the integrity of the outer mitochondrial membrane.
  • Their precise mechanism of action remains under investigation.

Purpose of the Study:

  • To elucidate the mechanism by which Bcl-2 family proteins regulate mitochondrial outer membrane permeability.
  • To evaluate the two proposed models: autonomous pore formation versus interaction with the permeability transition pore complex.

Main Methods:

  • Review and critical analysis of existing literature on Bcl-2 family function.
  • Biophysical and biochemical data interpretation regarding mitochondrial membrane permeabilization.

Main Results:

  • Evidence supports the model where Bcl-2 proteins directly form pores in the outer mitochondrial membrane.
  • The alternative model involving collaboration with the permeability transition pore complex is less supported by current data.

Conclusions:

  • The Bcl-2 family proteins likely act as autonomous pore-forming units to control mitochondrial outer membrane permeability.
  • This mechanism is crucial for the regulation of programmed cell death.

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