A cross section of muscle showing the molecular organization within the muscle fiber. In normal musc

A cross section of muscle showing the molecular organization within the muscle fiber. In normal muscle (inset), dystrophin provides a flexible and elastic connection between actin and the muscle fiber plasma membrane that helps dissipate the force of muscle contraction. In Duchenne muscular dystrophy, dystrophin is absent, resulting in tearing of the plasma membrane during contraction and the subsequent death of muscle fibers.


Muscle cell
membrane
/ Actin (thin) filament
Muscle filaments
Muscle fiber (cell)
Bundle of muscle fibers