ENO3 is also known as beta enolase, one of the three enolase isoenzymes found in mammals. A switch from alpha enolase to beta enolase occurs in muscle tissue during development and ENO3, a homodimer, is found in skeletal muscle cells in the adult and appears to have a function in striated muscle development and regeneration. Mutations can result in decreased stability of the enzyme and be associated with a glycogen storage myopathy. This results in exercise-induced myalgias, generalized muscle weakness and fatigability.