Figure 7. Syntaxin 4, Synaptotagmin 4, and Neuroligin 1 regulate acute structural plasticity at the NMJ.

(A–J) Representative images of NMJs stained with antibodies to HRP (magenta) and the postsynaptic marker Dlg (green) to highlight synaptic boutons. Ghost bouton budding was stimulated with spaced incubations in high K⁺. Ghost boutons are identified as round HRP+ structures lacking Dlg signal (arrowheads); images are shown from precise excision control (A), Syx4⁷³/+ (B), Syt4^BA1/+ (C), Nlg1^ex3.1/+ (D), Syx4⁷³ (E), Syt4^BA1 (F), Nlg1^ex3.1 (G), Syx4⁷³/+ Syt4^BA1/+ (H), Syx4⁷³/+ Nlg1^ex3.1/+ (I), and Syt4^BA1/+ Nlg1^ex3.1/+ (J) animals. (K) Quantification of ghost bouton number per NMJ from animals without (−) or with (+) high K⁺ stimulation. Data are presented as mean ± SEM. Scale bars = 20 μm (A–J), 6.7 μm (A′–J′). Statistical comparisons are fully described in Figure 7—source data 1, and are indicated here as ***p<0.001, **p<0.01, *p<0.05, ns = not significant; comparisons are with control unless indicated.

DOI: http://dx.doi.org/10.7554/eLife.13881.021

Figure 7—figure supplement 1. Interaction experiments between Syt4 and Nlg1.

(A) No genetic interactions are detected between Syt4 and Nlg1 with respect to bouton number. Data are presented as mean ± SEM, ns = not significant, ANOVA. Control refers to a precise excision control line for the Syt4^BA1 allele. (B–C) Representative NMJs expressing Nlg1-GFP in control (B) or Syt4^BA1 (C) backgrounds. (D) Quantification of GFP fluorescence intensity per HRP fluorescence intensity, in animals expressing Nlg1-GFP in control or Syt4^BA1 backgrounds. Data are presented as mean ± SEM, ns = not significant, Student’s t test. Scale bars = 5 μm. Sample size (n), mean, SEM, and pairwise statistical comparisons are presented for the data in (A) and (D).

DOI: http://dx.doi.org/10.7554/eLife.13881.023