myosin

This term refers to a specialized class of motor proteins that convert chemical energy into mechanical work. In muscle tissue, it functions as the thick filament that pulls against actin to shorten the muscle fiber, creating the physical force of contraction. Beyond muscle movement, these proteins act as intracellular transporters. They navigate the cytoskeleton to move organelles, vesicles, and other cellular cargo to specific destinations, functioning like a molecular railway system within the cell.