Mitochondrial morphology is dynamic and varied

The morphology of mitochondria is dynamic, often changing within a cell and from one cell type to the next. In the past few years, significant advances have been made in the study of mechanisms that help determine the morphologies of mitochondria and their intracellular distributions. It has become apparent that the distribution of mitochondria is determined by movement along the cytoskeleton, driven by molecular motors, and attachment to the cytoskeleton, using specific connector proteins. However, not all cells use the same cytoskeletal elements and motor proteins for mitochondrial movement and attachment. The shapes of mitochondria are also influenced by the extent of mitochondrial division and fusion. A number of proteins that affect mitochondrial division and fusion were recently discovered. Here, we review the proteins involved in the distribution and morphology of mitochondria and discuss how they may be physiologically regulated.