Figure 5. Neuronal overexpression of VAP^wt but not VAP^P58S leads a reduction in active zones.

(A–C) Confocal images of synapses at muscle 4 stained with anti-HRP (red) and nc82, which labels the active zone protein bruchpilot (brp, green). Control (A) and elav-GAL4/UAS-VAP^P58S (C) animals showed similar numbers of nc82 immunoreactive puncta per synapse. In contrast, such puncta were fewer in elav-GAL4/UAS-VAP^wt animals (B). (D) A histogram showing the difference in number of nc82 positive puncta in all 3 genotypes. In elav-GAL4/UAS-VAP^wt animals, an average of 142±14 puncta per synapse were observed (n = 18) as compared to 199±8.4 (n = 17) and 199±12 (n = 16) in control and elav-GAL4/UAS-VAP^P58S animals, respectively (*, different from other two genotypes, p<0.001, ANOVA with Sidak-Holm test). n.s., not significant. Scale bar, 10 µm