A pore is a pore is a pore (or a hub?): VDAC oligomerization in mitochondrial connectivity and modulation

Vito De Pinto1, Giuseppe Battiato1, Stefano Conti-Nibali1

  • 1Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy.

Insights

Voltage-dependent anion-selective channels (VDACs) are now understood as multifunctional signaling hubs, not just simple pores. Their complex roles and structures offer new therapeutic targets for mitochondrial diseases.

Area of Science:

  • Mitochondrial Biology
  • Structural Biology
  • Molecular Medicine

Background:

  • The voltage-dependent anion-selective channel (VDAC) was historically viewed as a passive pore in the outer mitochondrial membrane.
  • Discovery of three mammalian isoforms (VDAC1-3) revealed diverse cellular functions beyond metabolite transport.

Purpose of the Study:

  • To review recent structural, functional, and pharmacological advances in VDAC biology.
  • To highlight VDAC's role as a multifunctional signaling hub and therapeutic target.
  • To emphasize VDAC oligomerization dynamics and isoform specificity in mitochondrial regulation.

Main Methods:

  • Cryo-electron microscopy for high-resolution VDAC structure determination within native complexes.
  • Investigation of VDAC's phospholipid scrambling and outer membrane permeabilization functions.
  • Structural analysis of VDAC interactions with small molecules and macromolecules.

Main Results:

  • High-resolution structures reveal VDACs in native protein complexes.
  • VDACs exhibit novel functions like phospholipid scrambling and regulating outer membrane permeabilization via oligomers.
  • Interactions with small molecules and macromolecules are structurally defined.

Conclusions:

  • VDACs are multifunctional signaling hubs with significant therapeutic potential.
  • Oligomerization dynamics and isoform specificity are key to VDAC's role in mitochondrial function.
  • Emerging VDAC modulators offer therapeutic strategies for mitochondrial dysfunction-related diseases.

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