Project description:Transcriptomes of dissected brains from alate virgin and de-alate mated queens from polygyne fire ants were analyzed and compared. Four replicates of each condition were obtained. Thirteen genes were upregulated in mated queen brain and nine were downregulated. We found that for four differentially expressed genes in brain selected for qPCR analyses, changes in gene expression were most likely driven by the changes in physiological state (i.e. age, nutritional status or dominance rank) or in social environment (released from influence of primer pheromone).
Project description:Caffeine, a widely occurring plant alkaloid, has been shown to exhibit antimicrobial properties and influence insect behaviour. This study investigates the potential of caffeine to mitigate the effects of the fungal pathogen Beauveria bassiana in colonies of the ant Formica fusca. Using field-collected colonies, we examined the impact of a naturally relevant caffeine concentration (100 ppm) on ant survival, foraging behaviour, and gene expression under fungal exposure. Caffeine consumption delayed peak mortality and altered foraging dynamics in exposed ants, although it did not prevent fungal spore germination at the tested concentration. Transcriptomic analysis revealed significant upregulation of immune- and metabolism-related genes in exposed ants, alongside changes in genes linked to feeding behaviour and symbiotic interactions. While caffeine was a deterrent to sham-treated ants, exposed ants did not exhibit avoidance/preference. Additionally, caffeine demonstrated antifungal activity at higher concentrations, suggesting potential disruption of fungal development. These findings highlight the complex interplay between dietary compounds, pathogen defence, and ant behaviour, emphasizing the role of plant secondary metabolites in shaping insect-pathogen interactions.