(A-D) representative (10X) confocal images of whole mount brains immunolabeled with anti-Mef2. In control flies (A, v15550/+; B, JF03115/+), expression of Mef2 was prominent in the calyx of the mushroom bodies (arrowheads) and at lower levels throughout the brain. Detection of Mef2 appeared to be reduced in flies pan-neuronally expressing Mef2 RNAi transgenes (C, elav-Gal4/+;v15550/+; D, elav-Gal4/+;JF03115/+) compared to brains from RNAi transgene control animals (A, B). (E and F) Quantitation of Mef2 immunolabeling. Pixel intensity derived from z-stacks of all images of whole brains was significantly reduced in flies expressing Mef2 RNAi transgenes (E, elav-Gal4/+;v15550/+; F, elav-Gal4/+;JF03115/+) compared to their respective RNAi transgene controls (students t-tests; panel E, p=0.0002; panel F, p<0.0001, n = 4–5). The quantitation provided in Figs. 4E and 4F is derived from numerous images representing all portions of 4–5 brains per genotype.