Lack of Robustness of Life Extension Associated With Several Single-Gene P Element Mutations in Drosophila melanogaster

The hypothesis tested in this study was that single-gene mutations found previously to extend the life span of Drosophila melanogaster could do so consistently in both long-lived y w and standard w(1118) genetic backgrounds. GAL4 drivers were used to express upstream activation sequence (UAS)-responder transgenes globally or in the nervous system. Transgenes associated with oxidative damage prevention (UAS-hSOD1 and UAS-GCLc) or removal (EP-UAS-Atg8a and UAS-dTOR(FRB)) failed to increase mean life spans in any expression pattern in either genetic background. Flies containing a UAS-EGFP-bMSRA(C) transgene associated with protein repair were found not to exhibit life extension or detectable enhanced green fluorescent protein (EGFP) activity. The presence of UAS-responder transgenes was confirmed by PCR amplification and sequencing at the 5 and 3 end of each insertion. These results cast doubt on the robustness of life extension in flies carrying single-gene mutations and suggest that the effects of all such mutations should be tested independently in multiple genetic backgrounds and laboratory environments.