Microarray Expression Analysis of Ethanol-reared Drosophila melanogaster

The purpose of our research is to identify targets of ethanol exposure during development, using an existing Drosophila model of Fetal Alcohol Spectrum Disorder (FASD). We have previously shown that Drosophila raised on ethanol-treated food exhibit physical and behavioral defects commonly associated with FASD in humans. We are now attempting to identify the molecular, cellular and biochemical pathways responsible for regulating these phenotypes.

As one approach to identification of target genes for further investigation, we have performed a microarray-based mRNA expression analysis. We reared wild-type flies on food containing 7% ethanol by volume (as well as control food with no ethanol) and extracted RNA from 3rd instar wandering larvae. The RNA was then labeled and hybridized to Affymetrix Drosophila GeneChip 2.0 microarrays.  Preliminary analysis of the microarray data shows strong evidence for altered expression levels in genes that regulate lipid metabolism, olfaction, oxidative stress, and responses to environmental toxins. We hypothesize that the aforementioned pathways are involved in mediating the physical and behavioral phenotypes of ethanol-reared flies. The conclusions we draw from analysis of the microarray data will also provide us with a comprehensive list of the gene targets for future research.