Expression profile of CAPA, DH31, and DH44 hormones and seven GPCRs in the digestive system and survival in the Drosophila suzukii after feeding on non-nutritive sugars

Authors: PRICE, BRIANA - Washington State University; Parks, Ryssa; JANG, HYO SANG - Oregon State University; YOON, HOJUNG - Oregon State University; Lee, Jana; Choi, Man

Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/18/2025
Publication Date: 5/9/2025
Citation: Price, B.E., Parks, R.K., Jang, H., Yoon, H., Lee, J.C., Choi, M.Y. 2025. Expression profile of CAPA, DH31, and DH44 hormones and seven GPCRs in the digestive system and survival in the Drosophila suzukii after feeding on non-nutritive sugars. Annals of the Entomological Society of America. https://doi.org/10.1093/aesa/saaf014.
DOI: https://doi.org/10.1093/aesa/saaf014

Interpretive Summary: Spotted-wing drosophila (SWD) is an invasive vinegar fly that is a major threat to the small fruits industries worldwide and alternative control measures are needed. Our previous studies revealed SWD died quicker when the fly fed non-nutritive sugars such as erythritol and sucralose and that applications these sugars to fruit could be a non-toxic SWD control method. In this study, we identified the gene expressions of the diuretic hormones and their receptors in the non-nutritive sugar-fed fly. The findings provide toxicological data needed to identify biological targets for using bioactive proteins for SWD control.

Technical Abstract: Erythritol is a non-nutritive sugar alcohol and an active ingredient in artificial sweetener. In the past decade, erythritol has been demonstrated as insecticidal across several arthropod species. When insects consume erythritol, there is a physiological change that impacts their ability to regulate fluid secretion and water balance, causing an osmotic imbalance in the body. Erythritol can be combined with sucrose or non-nutritional sucralose to entice feeding in one of the most economically important pests to small fruits, spotted-wing drosophila, Drosophila suzukii. Our previous studies revealed D. suzukii will die quicker and excrete or desiccate more when feeding on a mixture of erythritol and sucralose. Insect neuropeptides such as diuretic hormone (DH) 31 and 44 (DH31 and DH44, respectively), and anti-diuretic hormone (ADH) CAPA, are known to control fluid secretion, water regulation, and ion balance by Malpighian tubules (MT). Maintenance of homeostasis with absorption by the midgut, diuresis and secretion by MT, and re-absorption by the hindgut occur in the insect digestive system. With our serial reports on non-nutritive sugar effects on Drosophila suzukii, and the identification of CAPA, DH31, and DH44 hormones and corresponding receptors from the fly, we hypothesized that the physiological regulation of ADH and DHs with their receptors would be altered in the non-nutritive sugar-fed fly (NSF). Our study results demonstrated that the expression of the three hormones was unregulated, whereas their receptors exhibited overall down-regulation in NSF. In addition, the injection of DH44 into the NSF significantly increased fly mortality, especially DH44. The genetic and physiological results facilitate molecular insights into the further development of new pest management tools.