Mitochondria tether to Focal Adhesions during cell migration and regulate their size

Mitochondria are the key generators of ATP in a cell. Visually, they are highly dynamic organelles that undergo cellular fission and fusion events in response to changing cellular energy requirements. Mitochondria are now emerging as regulators of mammalian cell motility. Here we show that mitochondria infiltrate the leading edge of NIH3T3 fibroblasts during migration. At the leading edge, we find that mitochondria move to and tether to Focal Adhesions (FA). FA regulate cell migration by coupling the cytoskeleton to the Extracellular Matrix through integrin receptors. Importantly, we find that inhibition of mitochondrial ATP generation concomitantly inhibits FA size. This suggests that mitochondrial energy production regulates migration through FA control.