Title: Necrosis is a major driver of thermal stress-induced mortality in Drosophila melanogaster larvae: cellular and molecular insights across acclimation phenotypes Authors: Fatemeh Saeidi & Hervé Colinet Affiliation: Université de Rennes, CNRS, ECOBIO (Ecosystèmes, biodiversité, évolution) – UMR 6553, 35000 Rennes, France This repository contains raw data files (in .txt format) associated with the study investigating cell death dynamics induced by cold (-3°C) and heat (38°C) stress in third-instar Drosophila melanogaster larvae. The study compared three acclimation phenotypes: - LNA: Non-acclimated larvae (reared at 25°C for 4 days) - LCA: Cold-acclimated larvae (reared at 15°C for 10 days) - LHA: Heat-acclimated larvae (reared at 30°C for 3 days) All data files are in tab-delimited text format (.txt). For detailed statistical methods, please refer to the Materials & Methods section of the associated manuscript. LNA : Non-acclimated larvae (reared at 25°C for 4 days) LCA : Cold-acclimated larvae (reared at 15°C for 10 days) LHA : Heat-acclimated larvae (reared at 30°C for 3 days) BS : Black spots (melanized lesions) NBS : No black spots Co : Unstressed control CTCF : Corrected total cell fluorescence ROS : Reactive oxygen species GLM : Generalized linear model GLMM : Generalized linear mixed model PCA : Principal component analysis RpL32 : Reference gene used for normalization

The intensification of agriculture, based on massive use of pesticides, led to the widespread contamination of terrestrial ecosystems. Although soil contaminations with pesticide residues have been demonstrated, their impacts on terrestrial biotic interactions remain unclear. To address this matter, we studied the effects of an environmental dose of a photosynthesis inhibitor herbicide (isoproturon) on an isoproturon-degrading soil bacteria-poacea-aphid system in the lab, mimicking below and aboveground interactions within buffer strips. We found that isoproturon and its main degradation product flow through this system, accumulating in plant shoots. No macroscopic effect of the herbicide was observed but metabolic shifts occurred in both plants (especially when exposed for a short time) and phytophages. Inoculation of isoproturon-degrading bacteria in the substrate suppressed most of these effects but some metabolic reshuffles in the longer run suggest secondary effects of Isoproturon degradation products. Moreover, inoculation of the non-degrading bacterial strain also impacted plant metabolism, underlying the close link between soil microbiota and aboveground organisms. This study shows that pesticide residues can transfer in terrestrial trophic networks, altering the physiology of each biological level, and highlights the importance of considering plant-bacteria interactions when assessing the response of semi-natural ecosystems to chronic contamination. (2025-02-11)