MYO19 encodes myosin-19, an actin-based motor protein that serves as a critical regulator of mitochondrial dynamics and positioning. The protein localizes to the mitochondrial outer membrane through a unique 30-45 residue motif and functions as an ATPase-driven motor that moves toward the plus-end of actin filaments 1 2. MYO19 interacts with Miro1/2 proteins, which serve as mitochondrial membrane receptors, and this interaction is essential for multiple mitochondrial functions 3 4. The motor plays crucial roles in mitochondrial transport to cellular projections, particularly stress-induced filopodia, and is required for proper mitochondrial inheritance during cell division 1 2. MYO19 regulates mitochondrial inner membrane architecture, specifically cristae organization, and maintains endoplasmic reticulum-mitochondria contact sites 5 4. Loss of MYO19 results in altered mitochondrial morphology, reduced oxygen consumption rates, and decreased abundance of OXPHOS supercomplexes 4. The protein exhibits unique kinetic properties with a relatively high duty ratio, suggesting it may function in small ensembles to generate sustained force for mitochondrial positioning and transport 6 7. These functions make MYO19 essential for mitochondrial homeostasis and cellular energy metabolism.