Author(s): Andrew Call
Mentor(s): John Chaston
Institution BYU
Understanding Drosophila feeding and choice preferences offers valuable insight into the genetic and environmental factors that shape dietary behaviors in animals, making it a powerful model for studying how genetics influence food selection. This study reveals genetic factors underlying Drosophila melanogaster preference for beneficial gut bacteria, offering new insights into how host genetics influence dietary preferences for lactic acid bacteria. Previous studies have defined myriad genes involved in fly feeding behaviors and preferences. In this study, we characterized fruit fly genes that contribute to the flies’ preference to consume Lactic Acid Bacteria (LAB), common inhabitants of the fruit fly gut, from their diets. We first screened a laboratory CantonS fly line for its preference to choose between diets inoculated with different types of microorganisms. Among these, we found that the strongest preference was manifest in flies choosing between diets inoculated with LAB and uninoculated diets, using a FlyPAD device to measure fly feeding preferences. Then, we screened ~100 lines from the Drosophila Genetic Reference Panel for their preference to feed on LAB vs. uninoculated diets. Most, but not all, lines preferred to consume diets inoculated with LAB. Then, we performed a genome wide association (GWA) to identify candidate fly genes responsible for this phenotype. We identified several candidate genes that contribute to these LAB preference phenotypes. We are currently working to validate the GWA predictions and have confirmed at least two genes that determine flies’ elevated preference for LAB. Together, these results provide insight into the genetic basis of microbiome-influenced feeding behaviors in fruit flies. By characterizing the genes associated with a preference for Lactic Acid Bacteria, we also enhance our understanding of how host organisms can be genetically predisposed to select specific microbial partners through dietary choices. This work contributes to a broader understanding of the genetic basis for host-microbiome interactions.