Proteinkinase C regulates motility of mitochondria

Mitochondria functions in cells depend on their localization and distribution that often coincide with regions of the highest consumption of ATP. Transport of mitochondria along microtubules and actin microfilaments, as well as their anchoring to different cytoskeletal structures, are strictly controlled in a cell. Using video microscopy of live cells expressing fluorescent mitochondrial marker we analyzed changes in the motility of these organelles caused by modulations of the proteinkinase C (PKC) activity. TPA-induced activation of PKC enhanced mitochondrial motility, while the PKC inhibitor bis-indolylmaleimide completely stopped the mitochondrial movements. The activating effect of TPA was not due to its influence on actin cytoskeleton, since the TPA effect persisted after the disruption of F-actin induced by Latrunculin B. Interestingly, in murine cell line MFT-16 devoid of vimentin intermediate filaments, TPA had no activating effect on the mitochondrial motility. Thus, our data indicate that PKC regulates interactions of mitochondria with intermediate filaments.