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Tubulin is an inherent component of mitochondrial membranes that interacts with the voltage-dependent anion channel

Manon Carré1, Nicolas André, Gérard Carles

  • 1UMR CNRS 6032, UFR Pharmacy, University of La Méditerranée, 27 Boulevard Jean Moulin, 13005 Marseille, France.

The Journal of Biological Chemistry
|June 28, 2002
PubMed

Insights

Mitochondria contain inherent tubulin, a protein crucial for cell structure. This mitochondrial tubulin interacts with the permeability transition pore, suggesting a role in apoptosis.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Anti-tubulin agents trigger cytochrome c release from mitochondria.
  • Tubulin's presence and function within mitochondria remain largely uncharacterized.

Purpose of the Study:

  • To investigate the presence and localization of tubulin within human mitochondria.
  • To characterize the specific tubulin isotypes and their interactions within mitochondria.

Main Methods:

  • Isolation of mitochondria from human cell lines.
  • Biochemical assays to confirm tubulin's inherent mitochondrial localization.
  • Electron microscopy for subcellular localization.
  • Tubulin isotype analysis.
  • Immunoprecipitation to identify interacting proteins.

Main Results:

  • Tubulin is an inherent component of mitochondria across various human cell types.
  • Mitochondrial tubulin is localized to mitochondrial membranes and distinct from cytosolic tubulin.
  • Specific tubulin isotypes (acetylated, tyrosinated alpha-tubulin, class III beta-tubulin) are enriched in mitochondria.
  • Mitochondrial tubulin specifically associates with the voltage-dependent anion channel (VDAC).

Conclusions:

  • Tubulin is an integral component of mitochondrial membranes.
  • Mitochondrial tubulin's association with VDAC suggests a role in regulating mitochondrial permeability and apoptosis.

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