The proposed research will probe into the requirement of manganese-superoxide dismutase [MnSOD] in aging and tissue damages thereof through some unique mutant models in Drosophila. These mutant models will be used to (1) investigate the effect of overexpression of MnSOD in different tissues in a directed fashion, testing the hypothesis that overexpression of MnSOD in specific tissue or cell types extends the life span by offering increased protection against oxidative damage; (2) investigate the effect of loss of MnSOD function in specific tissue or cell types, testing the hypothesis that loss of MnSOD function is associated with increased oxidative stress causing accelerated tissue damages; (3) investigate the effects of missense mutations in MnSOD gene, testing the hypothesis that like in familial amyotrophic lateral sclerosis (FALS) patients, altered MnSOD activity could cause neuropathology and degenerative tissue damages.