Superoxide dismutase 2 (Mn) (Sod2) encodes an enzyme that detoxifies superoxide radicals in mitochondria. The loss of Sod2 generates endogenous oxidative stress that results in reduced activity of critical mitochondrial enzymes, hypersensitivity to oxidative stress and neonatal lethality. A muscle restricted
p38Kinase-Mef2-Sod2 signaling module influences life span and stress.