A correlation between DNA repair capacity and longevity in adult Drosophila melanogaster

Mutagen-sensitive (mus) mutants in Drosophila melanogaster have been biochemically characterized as defective in DNA repair. Life spans of three temperature-sensitive mus strains have been measured to determine if loss of DNA repair capacity has a substantial influence on the longevity of adult Drosophila. The mus(ts) strains have been tested for an effect on longevity, with and without exposure to low doses of the alkylating agent methyl methanesulfonate. All three strains tested show substantially reduced life spans in the absence of the mutagen. The effect is seen at the restrictive temperature but not at the permissive temperature. In addition, the reduction in life span is enhanced by exposure to very low, sublethal doses of MMS during development. This effect is also temperature-sensitive. Temperature-shift studies indicate that it is mutagen-sensitivity during development that is leading to reduced longevity in adults. These results suggest that the integrity of DNA repair systems may play a role in the longevity of adult Drosophila melanogaster.