Viability assays

For embryo viability counts, 2 to 3-day old virgin female flies were mated to wild-type males for 24 h and 15 females (in triplicate) were placed in egg-collection chambers to lay eggs during a 18 h period, then the laying plate was removed and eggs counted. All embryos were counted and kept on an agar surface at 20 °C for 48 h and hatchability of those eggs was calculated at that point by counting the unhatched embryos. In all plates, females laid between 211 and 332 eggs. Each experiment was carried out in triplicate, and the results presented are averages from these three experiments. For adult fly counts, the larvae obtained in each embryo count assay replicate were transferred from egg collection plates to 250 ml bottles containing modified cornmeal medium. All adult flies that emerged from these bottles were counted and the results of the three replicates for each experiment averaged together. Egg-to-larvae and egg-to-adult ratios were calculated by normalizing the experimental values to the survival observed in parallel experiments carried out with WT flies.