Figure 1. Synaptic overgrowth in nwk is dominantly enhanced by endocytic mutations.

(A–H) Confocal images of NMJ 4 labeled with FITC-conjugated anti-HRP. (A) Wild-type NMJs are relatively unbranched and contain few satellite boutons. (B) nwk NMJs are more branched than wild type and have increased numbers of total boutons and satellite boutons. (C–D) Loss of one copy of endo has no effect on total and a small effect on satellite bouton formation in a wild-type background (C), but results in a large increase in both parameters in a nwk background (D). (E–F) Loss of one copy of dap160 does not affect bouton number or satellite bouton formation in a wild-type background (E), but leads to a significant increase in total and satellite bouton number in nwk mutants (F). (G–H) At the semi-restrictive temperature of 25°C, heterozygosity for shi does not affect total or satellite bouton number at wild-type NMJs (G), but in a nwk background, total bouton number and satellite bouton formation are significantly increased (H). (I–J) Quantification of total (I) and satellite (J) bouton number at NMJ 4 in wild type, nwk^1/2, endo²⁷³⁰/+, endo²⁷³⁰ nwk²/+ nwk¹, dap160^Δ1/+, dap160^Δ1/+; nwk^1/2, shi^ts1/+, and shi^ts1/+; nwk^1/2 backgrounds. * p < 0.05, ** p < 0.01, *** p < 0.001. P-values above individual bars refer to comparisons between nwk and the indicated genotype. Arrows in B point to examples of satellite boutons. Scale bar equals 20 µM.