Genetic and genomic response to selection for food consumption in Drosophila melanogaster

Food consumption is critical for animal survival and reproduction. The biomedical and economic consequences of metabolic diseases arising from excessive food intake, however, are a burden for human society. While the role of neuroendocrine feedback loops, food sensing modalities, and physiological state in regulating food intake are increasingly well understood, other genetic mechanisms remain elusive. Here, we applied ten generations of artificial selection for high and low food consumption in replicate populations of Drosophila melanogaster. The phenotypic response to selection was highly asymmetric, with efficient selection and an average realized heritability of 0.15 in the lines selected for high food consumption. To further nominate candidate genes contributing to response to selection for feeding behavior, we evaluated differences in genome wide gene expression between the selection lines using whole-fly RNA sequencing. We identified 1,631 differentially expressed genes in the analysis pooled across sexes, and 1,267 (2,321) differentially expressed genes in females (males). We applied an ‘evolve and re-sequence’ approach, combined with analysis of divergence in genome wide gene expression to identify strong candidate genes affecting transcriptional regulation of food consumption. We performed ten generations of replicated, divergent artificial selection for high and low food consumption using an advanced intercross population (AIP) derived from as subset of Drosophila Genetic Reference Panel (DGRP) lines as the base population. We performed RNA sequencing of pools of individuals from two replicate lines for both high and low selection at two generations (G9 and G10).