In yeast, Ca2+ and octylguanidine interact with porin (VDAC) preventing the mitochondrial permeability transition.
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.
Gutiérrez-Aguilar
Manuel
M
Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 México D. F., Mexico.
Pérez-Vázquez
Victoriano
V
Bunoust
Odile
O
Manon
Stéphen
S
Rigoulet
Michel
M
Uribe
Salvador
S
D002118:Calcium / Q000737:chemistry / Q000378:metabolism*; D002413:Cations, Divalent / Q000737:chemistry; D002463:Cell Membrane Permeability / Q000187:drug effects; D017353:Gene Deletion; D006146:Guanidines / Q000494:pharmacology*; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism*; D008933:Mitochondrial Swelling / Q000187:drug effects; D010100:Oxygen / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014638:Vanadates / Q000494:pharmacology; D050994:Voltage-Dependent Anion Channels / Q000235:genetics / Q000378:metabolism*
D002413:Cations, Divalent; D006146:Guanidines; D050994:Voltage-Dependent Anion Channels; C015403:octylguanidine; D014638:Vanadates; D010100:Oxygen; D002118:Calcium