Mitochondrial calcium spiking: a transduction mechanism based on calcium-induced permeability transition involved in cell calcium signalling.
We report reversible Ca(2+)-induced Ca2+ release from mitochondria, which takes the form of Ca2+ spikes. Mitochondrial Ca2+ spiking is an all-or-none process with a threshold dependence on both the frequency and the amplitude of the Ca2+ pulses used as stimuli. This spiking relies on the transient operation of the mitochondrial permeability transition pore, and is initiated--in a threshold-dependent manner--with inositol-triphosphate-mediated Ca2+ responses on permeabilized cells. Evidence that mitochondrial Ca(2+)-induced Ca2+ release contributes to inositol-triphosphate-mediated Ca2+ responses in intact cells is also reported.
Groupe d'Etude des Systèmes Biologiques Intégrés, D(BM)2, Universitè Bordeaux II, France.
F
F
Ichas
L S
LS
Jouaville
S S
SS
Sidash
J P
JP
Mazat
E L
EL
Holmuhamedov
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D008930:Mitochondria, Liver / Q000378:metabolism*; D010539:Permeability; D051381:Rats; D015398:Signal Transduction; D014407:Tumor Cells, Cultured
D002118:Calcium