Fast and chronic ethanol tolerance - time course

To better understand the molecular mechanisms underlying ethanol action we have developed an assay system to study sensitivity and fast and chronic tolerance to the sedative effects of ethanol. Flies developed fast ethanol tolerance after single exposure to 50% of ethanol vapor for 40 min. Flies can also develope chronic ethanol tolerance after 5x 40 min exposure to 50% ethanol vapor interspersed with 4x 80 min exposure to 10% ethanol vapor. We used microarray analysis to identify genes involved in the development of fast and chronic ethanol tolerance in Drosophila. More than 600 hundred genes were found to have changed their expression level in response to different ethanol treatment. Among these genes, Homer was picked for further study and is demonstrated that its expression in ellipsoid body is critical for the normal sensitivity and fast toleance to ethanol. Keywords: time course Whole heads of 3 groups of Drosophila were separated for RNA extraction and hybridization on Affymetrix microarrays. These 3 groups of flies were treated with different ethanol treatment. Naive group of flies (GSM101531, GSM101532, GSM101533, GSM101534, GSM101535, GSM101536) received only 50 min of humidified air. Fast group of flies (GSM101537, GSM101538, GSM101539, GSM101540, GSM101541, GSM101542) received humidified air for 50 min followed by a single exposure of 50% ethanol vapor for 40 min. Chronic group of flies (GSM101543, GSM101544, GSM101545, GSM101546, GSM101547, GSM101548) ) received humidified air for 50 min followed by 5 exposures of 50% ethanol vapor for 40 min.