Transcriptome profiling of Drosophila motor neurons with age. Transcriptome profiling of Drosophila motor neurons with age

The purpose of this array was to investigate age-dependent changes the transcriptome of a highly homogenous cell population (Drosophila motor neurons) in order to help understand the contribution of changes in gene expression to age-dependent motor deficiencies. Drosophila motor neurons expressing GFP (via the UAS-Gal4 binary expression system) were isolated using flow cytometry from flies that were 7, 35 or 45 days old. The microarray design was highly redundant for calcium-binding and ion channel genes as we had apriori reasons to believe changes in these genes would be important. The ages were chosen because previous work had identified a major shift in neurotransmitter release between the ages of 35 and 45 days in Drosophila motor neurons. Although no significant changes were identified in that window, several genes showed elevated expression in old (35 day and 45 day) motor neurons compared to young (7 day) including matrix metalloproteinase 1 (dMMP1). Overall design: For each age group, 5 or 6 biologically independent replicates were performed. Replicates were microarray hybridizations of transcripts from pools of approximately 10000 Drosophila motor neurons from 5 individual flies.