In yeast, Ca2+ and octylguanidine interact with porin (VDAC) preventing the mitochondrial permeability transition

Biochim Biophys Acta. 2007 Oct;1767(10):1245-51. doi: 10.1016/j.bbabio.2007.07.002. Epub 2007 Jul 19.

Abstract

In yeast, Ca(2+) and long chain alkylguanidines interact with mitochondria modulating the opening of the yeast mitochondrial unspecific channel. Mammalians possess a similar structure, the mitochondrial permeability transition pore. The composition of these pores is under debate. Among other components, the voltage-dependent anion channel has been proposed as a component of either pore. In yeast from an industrial strain, octylguanidine and calcium closed the yeast mitochondrial unspecific channel. Here, the effects of the cations Ca(2+) or octylguanidine and the voltage-dependent anion channel effector decavanadate were evaluated in yeast mitochondria from either a wild type or a voltage-dependent anion channel deletion laboratory strain. It was observed that in the absence of voltage-dependent anion channel, the yeast mitochondrial unspecific channel was desensitized to Ca(2+), octylguanidine or decavanadate but remained sensitive to phosphate. It is thus suggested that in yeast mitochondria, the voltage-dependent anion channel has a cation binding site where Ca(2+) and octylguanidine interact, conferring cation sensitivity to the yeast mitochondrial unspecific channel.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium / chemistry
  • Calcium / metabolism*
  • Cations, Divalent / chemistry
  • Cell Membrane Permeability / drug effects
  • Gene Deletion
  • Guanidines / pharmacology*
  • Intracellular Membranes / drug effects
  • Intracellular Membranes / metabolism
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria / drug effects*
  • Mitochondria / metabolism*
  • Mitochondrial Swelling / drug effects
  • Oxygen / metabolism
  • Saccharomyces cerevisiae / chemistry
  • Saccharomyces cerevisiae / drug effects*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Sensitivity and Specificity
  • Vanadates / pharmacology
  • Voltage-Dependent Anion Channels / genetics
  • Voltage-Dependent Anion Channels / metabolism*

Substances

  • Cations, Divalent
  • Guanidines
  • Voltage-Dependent Anion Channels
  • octylguanidine
  • Vanadates
  • Oxygen
  • Calcium