Filter circles

To measure stress responses, 100 newly eclosed flies (20 flies per vial) were kept on a standard cornmeal medium at 25°C for 2 days [3 (link),5 (link),26 (link)]. For the starvation test, these 2-day-old adult flies were transferred to new vials (2.5 × 9.3 cm) containing two filter circles (2.4-cm diameter, Fisher Scientific) soaked in 300 μl of distilled water, and were maintained at 25°C under moist conditions with 100 μl of water added every 12 hrs. For the oxidative stress test, the 2-day-old adult flies were starved for 6 hrs at 25°C as described above. The flies were then transferred to new vials containing two filter circles wetted with 300 μl of 20 mM methyl viologen hydrate (Paraquat, Fisher Scientific) in a 5% sucrose solution and maintained at 25°C. For the heat test, the 2-day-old adult flies were transferred to new vials containing standard cornmeal medium and maintained at 37°C with 30% humidity. The median survival times of flies under each stress (starvation, oxidation, or heat) were calculated from the survival curves of 4 ~ 8 independent experiments.

To measure stress responses, 100 newly enclosed flies (20 flies per vial) were kept in a standard cornmeal medium at 25°C for 2 days [9 (link),19 (link),50 (link)]. For the heat test, these 2-day-old adult flies were transferred to new vials containing standard cornmeal medium and maintained at 37°C with 30% humidity. For the starvation test, the 2-day-old adult flies were transferred to new vials (2.5 × 9.3 cm) containing two filter circles (2.4-cm diameter, Fisher Scientific) soaked in 300 μl of distilled water, and were maintained at 25°C under moist conditions with 100 μl of water added every 12 hrs. For the oxidative stress test, the 2-day-old adult flies were starved for 6 hrs at 25°C as described above. Then, the flies were transferred to new vials containing two filter circles wetted with 300 μl of 20 mM methyl viologen hydrate (Paraquat, Fisher Scientific) in a 5% sucrose solution and maintained at 25°C. The median survival times of flies under each stress (heat, starvation, or oxidation) were calculated from the survival curves of 3 ~ 6 independent experiments. For the aging test, 200 virgin flies (20 flies per vial) were counted and transferred to fresh standard cornmeal vials every 3 - 4 days [9 (link)]. Mean lifespan was calculated from the lifespan curves and averaged with standard error of mean (SEM) from several repeat experiments.