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Mitochondrial membrane permeabilization by HIV-1 Vpr

Aurélien Deniaud1, Catherine Brenner, Guido Kroemer

  • 1CNRS FRE 2445, Université de Versailles/St Quentin, 45, avenue des Etats-Unis, 78035 Versailles, France.

Mitochondrion
|August 27, 2005
PubMed

Insights

Viral protein R (Vpr) targets mitochondria, directly interacting with the permeability transition pore complex (PTPC) and adenine nucleotide translocator (ANT) to induce apoptosis and mitochondrial membrane permeabilization (MMP).

Area of Science:

  • Molecular biology
  • Cell biology
  • Virology

Background:

  • Mitochondria are key targets for viral proteins that modulate apoptosis.
  • Viral Protein R (Vpr) is known to interact with cellular components to influence cell fate.

Purpose of the Study:

  • To elucidate the mechanism by which viral protein R (Vpr) induces apoptosis via mitochondrial pathways.
  • To investigate the direct interaction of Vpr with the mitochondrial permeability transition pore complex (PTPC).

Main Methods:

  • Investigated Vpr interaction with PTPC components, specifically the adenine nucleotide translocator (ANT).
  • Utilized peptide inhibition and nucleotide binding assays (ADP, ATP) to confirm direct Vpr-ANT interaction.
  • Assessed the role of Bcl-2 in modulating the Vpr-PTPC interaction.

Main Results:

  • Vpr directly interacts with ANT, a component of the PTPC.
  • This Vpr/ANT interaction forms large conductance channels, inducing mitochondrial membrane permeabilization (MMP).
  • The interaction is abolished by ANT-binding peptides, ADP, ATP, and Bcl-2, confirming direct functional modulation.

Conclusions:

  • Viral protein R (Vpr) directly targets mitochondria by interacting with the PTPC, specifically ANT.
  • Vpr binding to ANT triggers the hallmarks of mitochondrial membrane permeabilization (MMP) and apoptosis.
  • These findings reveal a direct mechanism of Vpr-induced apoptosis through structural and functional modulation of PTPC proteins.

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