Figure 2. Molecular motor adaptor complexes mediate mitochondrial movement.

Motor proteins (red) facilitate mitochondrial (blue) movement along cytoskeletal tracks (gray) such as actin filaments or microtubules. Organelle-specific interactions are established by adaptor proteins (purple) that complex with the motor. Adaptors likely require integral outer mitochondrial membrane proteins to serve as receptors (green), allowing localization of the motor adaptor complex to the organelle.