D, E PER assay for control and Gr28bMi flies in the (D) legs or (E) proboscis. Flies were initially given 2% sucrose, then 2% sucrose in combination with 5% saponin (n = 4). The error bars represent SEMs. The asterisks indicate significant differences from that of the control detected by a single-factor ANOVA with Scheffe's analysis as a post hoc test to compare two sets of data (*P < 0.05, **P < 0.01). 