Nice songs, good smells: overexpression of antioxidants in transgenic male fruit flies blunts radiation-induced oxidative stress and improves sexual signaling

Authors: SIMOES DIAS, VANESSA - International Atomic Energy Agency (IAEA); Bruton, Robert; Foreman, Everett; Mankin, Richard; Alborn, Hans; TEETS, NICHOLAS - University Of Kentucky; SCHETELIG, MARC - Justus-Liebig University; Handler, Alfred; HAHN, DANIEL - University Of Florida

Submitted to: Fruit Flies of Economic Importance International Symposium
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/3/2026
Publication Date: N/A
Citation: N/A

Interpretive Summary: Many species of fruit fly, including caribflies, are important pests of fruit worldwide. Scientists at the University of Florida, the Center for Medical, Agricultural, and Veterinary Entomology, the University of Kentucky, and Justus-Liebig-University developed methods to genetically overexpress antioxidant enzymes in caribflies reared for sterile insect technique (SIT) pest control programs that release sterile males to reduce wild caribfly populations. Caribflies are sterilized using ionizing radiation but that procedure increases oxidative stress, which reduces flight and mating activity. Genetically modified flies were developed that overexpress antioxidant enzymes, which restores the sterile fly healthiness. Such flies have greater mating success in wild populations than untreated flies, which makes SIT programs more effective.

Technical Abstract: The sterile insect technique (SIT) is an effective control method for insect pest populations based on the release of male insects sterilized by ionizing radiation to reduce reproduction of targeted females in the field. Although irradiation successfully sterilizes insects, it may induce oxidative stress that can diminish the sexual competitiveness of sterile males. Oxidative stress alters an organism's physiological state through an imbalance between free radicals and antioxidants. The surplus of free radicals generated by oxidative stress affects various reproductive traits, including courtship displays. In tephritid fruit flies, courtship behavior involves multimodal signaling, incorporating both chemical and acoustic elements that can be negatively impacted by oxidative stress. In this study, we hypothesized that enhancing antioxidant capacity would reduce oxidative stress and improve male courtship behavior in the Caribbean fruit fly, Anastrepha suspensa. We overexpressed a major antioxidant enzyme in A. suspensa, mitochondrial manganese-dependent superoxide dismutase (MnSOD), to test the extent to which increasing antioxidant capacity decreases the adverse effects of oxidative stress on male acoustic and chemical displays after irradiation. The results showed that males overexpressing MnSOD had greater mating success, produced more attractive calling songs, and generated higher quantities of essential pheromone compounds (Anastrephin and Epianastrephin) than wild-type males. These findings contribute to a better understanding of the evolution of multimodal signaling from a mechanistic perspective, as well as point to new directions for improving SIT programs.