Figure 4.
dnlg2 mutants display synapse differentiation defects with severely disorganized postsynaptic areas. A–G, TEM micrographs of wild type (A, B), dnlg2 mutants (C, D), and dnlg2 mutants with the genomic BAC construct (E), dnrx/Df (F), and dnlg2;dnrx/Df double mutants (G) showing the ultrastructural features of boutons at NMJ 6/7. AZ, PSAs, and SSR are highlighted. SSR widths were measured from PSD to the distal fold. Note that the number of AZs (arrows) is increased and PSAs fail to differentiate properly in dnlg2 mutants (C, D, PSA with arrows). H–K, Quantification of ultrastructural morphometric analyses on all genotypes. H, Compared with wild type, the AZ number in boutons is increased in dnlg2CL2 mutants. I, The lengths of PSD adjusted to the perimeter in dnlg2 mutants is also increased. PSAs are enlarged (J) and the widths of SSR are reduced (K) in dnlg2 mutants. ***p < 0.001; **p < 0.01; *p < 0.05 (Student's t test). Scale bars: 0.5 μm.