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The mitochondrial outer membrane protein import machinery: a new player in apoptosis?

Elise Petit1, Lisa Oliver, Francois M Vallette

  • 1Equipe 9, Centre de Recherche en Cancerologie Nantes-Angers (U892 INSERM), Nantes, cedex 01, France.

Frontiers in Bioscience (Landmark Edition)
|March 11, 2009
PubMed

Insights

Proteins of the BCL-2 family regulate apoptosis by acting at the mitochondria. Their interaction with the translocase of the outer membrane (TOM) complex is a newly explored mechanism in cell death.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The BCL-2 family of proteins (pBCL-2s) are key regulators of apoptosis, a programmed cell death pathway.
  • Mitochondria are central to apoptosis initiation and execution, serving as the primary site of pBCL-2s action.
  • pBCL-2s are localized to the mitochondrial outer membrane (MOM), either constitutively or upon apoptotic signaling.

Purpose of the Study:

  • To review current data on the mechanisms of pBCL-2 targeting and activation during apoptosis.
  • To discuss the potential role of interactions between pBCL-2s and the translocase of the outer membrane (TOM) complex in apoptosis.

Main Methods:

  • Literature review of existing studies on pBCL-2 proteins, apoptosis, and mitochondrial outer membrane protein import.
  • Analysis of recent findings regarding pBCL-2 interactions with TOM complex components.

Main Results:

  • pBCL-2s play a critical role in the mitochondrial pathway of apoptosis.
  • Emerging evidence suggests that pBCL-2s interact with the TOM complex, which mediates protein import across the MOM.
  • These interactions may influence the targeting and activation of pBCL-2s during apoptosis.

Conclusions:

  • The interaction between pBCL-2s and the TOM complex represents a novel area of investigation in apoptosis.
  • Understanding this interaction could elucidate previously unknown mechanisms governing programmed cell death.

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