Project description:Our objective was to determine whether gene expression in Drosophila melanogaster selectively bred for long or short night sleep duration changes detectably across generations. To meet this objective, we performed transcriptional profiling of ten pooled whole adult individuals from four selected populations and two control populations across 13 generations. We quantified differential expression among selection scheme (long sleep, short sleep, or unselected control), generation (generation 0; then generations 2-13), and sex for each gene.
Project description:<p>Chronic sleep loss profoundly impacts metabolic health and shortens lifespan, but studies of the mechanisms involved have focused largely on acute sleep deprivation. To identify metabolic consequences of chronically reduced sleep, we conducted unbiased metabolomics on heads of three adult Drosophila short-sleeping mutants with very different mechanisms of sleep loss: fumin (fmn), redeye (rye), and sleepless (sss). Common features included elevated ornithine and polyamines, with lipid, acyl-carnitine, and TCA cycle changes suggesting mitochondrial dysfunction. Studies of excretion demonstrate inefficient nitrogen elimination in adult sleep mutants, likely contributing to their polyamine accumulation. Increasing levels of polyamines, particularly putrescine, promote sleep in control flies but poison sleep mutants. This parallels the broadly enhanced toxicity of high dietary nitrogen load from protein in chronically sleep-restricted Drosophila, including both sleep mutants and flies with hyper-activated wake-promoting neurons. Together, our results implicate nitrogen stress as a novel mechanism linking chronic sleep loss to adverse health outcomes-and perhaps for linking food and sleep homeostasis at the cellular level in healthy organisms.</p>
Project description:A study evaluating the effect of stress resistance selection of Drosophila melanogaster. Abstract Here, we report a detailed analysis of changes in gene expression in Drosophila melanogaster selected for multiple eological relevant environmental stress resistance traits. We analyzed females from three biological replicates from seven selection regimes and one control regime using whole genome gene expression arrays. Replicated selection lines were selected for resistance to acute heat survival, high temperature knock down, constant 30°C during development, cold shock survival, desiccation and starvation, respectively. Additionally, a set of replicated lines was selected for increased longevity. When compared to gene expression profiles of control lines, we were able to detect consistent selection responses at the transcript level in each specific selection regime and also found a group of differentially expressed genes that were generally changed among all selected lines. Replicated selection lines clustered together, i.e. showed similar changes in gene expression (compared to controls) and thus showed that 10 generations of artificial selection gives a clear signal among gene expression profiles. The changes in gene expression in lines selected for increased longevity, desiccation and starvation resistance, respectively, showed high similarities. Cold resistance selected lines showed little differentiation from controls. Different methods of heat selection (heat survival, heat knock down and constant 30°C) showed little similarity verifying that different mechanism are involved in high temperature adaptation. The direction of change in gene expression in the selected lines showed a consistent pattern for each selection regime. For most selection regimes and in the comparison of all selected lines and controls exclusively up- or down regulation of gene expression among significant differentially expressed genes was found. The different responses to selection expressed in individual selection regimes and among all selected lines indicate that we have identified genes involved in stress specific and general stress response mechanisms. Keywords: control versus selected
Project description: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).
Project description:Thermal acclimation study on Drosophila melanogaster reared at 3 different temperatures (12, 25, and 31oC). The proteomic profiles of D. melanogaster under these different temperatures were analyzed and compared using label-free tandem mass spectrometry.