Project description:Drosophila melanogaster larvae reared on isocaloric diets with different protein/sugar ratios, exhibit different developmental times and the eclosed adults show different metabolite pools of glycogen and triglycerides (Matzkin et al., 2011, PMID: 21525254). To investigate the effect of larval diet on adult neurological processes at the gene expression level we performed high throughout RNA sequencing of fly heads reared in two different protein/sugar ratio diets.
Project description:This RNAseq study has been performed in the framework of a project using experimental evolution to understand the consequences of genetically-based adaptation to juvenile undernutrition for adult gene metabolism. Six "Selected" populations of Drosophila melanogaster had been maintained on a very poor larval diet (3.2 g yeast / liter w/v) for 14 years (about 250 generations). Six "Control" populations of the same origin had been maintained in parallel on the standard diet (12.5 g yeast/liter). In a factorial design, we performed RNAseq on flies from Selected and Control populations raised both standard and poor diet. This design separates the effects of the evolutionary differentiation between the two sets of populations, and the effect of the larval diet experienced by the focal individuals. Adults of all populations were transferred to standard diet within 24 h or emergence and maintained on it for 3 days before being collected for RNAseq. RNAseq was performed on carcasses of adult mated females (10 carcasses per sample), consisting mainly of the fat body and the abdominal body wall.
Project description:Genes with sex-biased expression in adults experience unique evolutionary dynamics. It is unclear, however, whether the selection pressures responsible for these well documented patterns also act upon genes with sex-biased expression in other developmental stages. To examine this, we measured expression in male and female Drosophila melanogaster larvae. Drosophila melanogaster wandering third instar larvae were sexed using the visible gonad. RNA was isolated from three replicate samples of male and female larvae and one sample each of adult males and females. RNA was prepared following the manufacturer's instructions, using single color labelling. Each sample/replicate was hybridized to one sector of the Agilent 4 sector array (a total of two arrays were used), with the following design: Array 1 had one larval male sample, one larval female sample, one adult male sample, and one adult female sample; Array 2 had two larval male samples and two larval female samples.
Project description:Metabolites are active controllers of cellular physiology, but their role in complex behaviors is less clear. Here we report the metabolic changes that occur during the transition between hunger and satiety in Drosophila melanogaster. To analyze these data in the context of fruit fly metabolic networks, we developed Flyscape, an open-access tool. We show that in response to eating, metabolic profiles change in quick, but distinct ways in the heads and bodies. Consumption of a high sugar diet dulls the metabolic and behavioral differences between the fasted and fed state, and reshapes the way nutrients are utilized upon eating. Specifically, we found that high dietary sugar increases TCA cycle activity, alters neurochemicals, and depletes 1-carbon metabolism and brain health metabolites N-acetyl-aspartate and kynurenine. Together, our work identifies the metabolic transitions that occur during hunger and satiation, and provides a platform to study the role of metabolites and diet in complex behavior.
Project description:Aim: mRNA profile of larval wing imaginal discs of Drosophila melanogaster to study the cooperation between Notch activation and loss of epithelial polarity (scrib mutation) during neoplastic growth. Results: The combination of Notch activation and scribble mutation (NS) results in mRNA expression changes that, while partly overlapping with Notch only (N), and with scrib mutation only (S), are unique to the combination
Project description:Our two main aims were 1) to isolate age-related changes in gene expression in females of the solitary insect, Drosophila melanogaster; and 2) to determine whether experimentally changing the shape of the fecundity-longevity relationship (by changing larvae diet) caused changes in age-related gene expression in these females. To address these aims we extracted RNA from three key tissues (fat body, head and ovary) from females at two time points (10% and 60% mortality phases). Each of these females had experienced one of two treatments: medium-quality larval diet (M) treatment (resulting in a positive fecundity-longevity relationship) and high-quality larval diet (H) treatment (resulting in a negative fecundity-longevity relationship).
Project description:The innate immune response of insects relies on several humoral and cellular mechanisms that require the activation of circulating proteases in the hemolymph to be functional. Here, we analyzed the gelatinase and caseinase activities of Drosophila larval hemolymph under normal and pathogenic conditions (bacterial lipopolysaccharides or endoparasitoid Leptopilina boulardi) using in gel zymography. Gelatinase activity was more intense than caseinase activity and qualitative and quantitative variations were observed between D. melanogaster strains and Drosophila species. Mass spectrometry identified a large number of serine proteases in gel bands equivalent to the major gelatinase and caseinase bands and of these, the most abundant and redundant were Tequila and members of the Jonah and Trypsin protease families. However, hemolymph from Tequila null mutant larvae showed no obvious changes in zymographic bands. Nor did we observe any significant changes in hemolymph gelatinases activity 24 h after injection of bacterial lipopolysaccharides or after oviposition by endoparasitoid wasps. These data confirmed that many serine proteases are present in Drosophila larval hemolymph but those with gelatinase and caseinase activity may not change drastically during the immune response.
Project description:Transcriptomes of Drosophila melanogaster eye-antennal imaginal discs at three sequential larval stages: late 2nd instar (72h after egg laying (AEL)), mid 3rd instar (96h AEL) and late 3rd instar (120h AEL).