Active zones in NMJs of third-instar female larvae with panneuronal sgg-RB overexpression (A,B) and sgg-RB overexpression in motor neurons (C,D). Control B, sggB denote hybrid genotypes obtained as a result of crossing the corresponding lines with the driver line D4 inducing the expression of transgenic constructs in the nervous system or the driver line D12 inducing the expression of transgenic constructs in motor neurons. A full description of genotypes is given in the Materials and Methods section. Representative confocal images of NMJs (muscle 4, hemi-segment 34–) stained for active zones (BRP, red) and neural membranes (HRP, green) (A,C). Bar = 10 µm. Quantification of the number of active zones (B,D). *** denotes p < 0.001 determined by the Kruskal-Wallis test.