Parashar, Vijay, Blanka Rogina, and Alan Lurie
Drosophila melanogaster (fruit fly) has been a model organism used for many genetics and developmental biology studies for over 100 years. Various studies have been conducted to understand the effects of ionizing radiation (IR) on Drosophila. Most IR studies have been done using early stages of development such as larvae and pupae. We examined the effects of IR on adult fruit flies at different ages. Male and female adult fruit fly were irradiated using different doses of IR and dose-response curves for lethality were prepared. 50% lethality 2 days post irradiation (LD50/2) in one-day-old adult fruit flies is observed to be ~1250Gy (Gray). Male flies are more radiation sensitive than female flies. We found that wild type fruit flies are 300 times more radiation-resistant compared to human, similarly to published data. In addition, we showed that there is an age dependent decline in the radiation resistance in both male and female adult flies.
We observed a synergistic effect on the lethality of flies exposed to lower dose of IR (200Gy) early in life and the treatment with paraquat, a known free radical producer, later in life (at age 10 or 20 days).
Our data suggest that adult Drosophila melanogaster can serve as an excellent model to study the factors responsible for high radiation resistance of fruit flies.