Neurotransmission defects at Dscam2 mutant NMJs. (A and B) Quantification of mEJP frequency (A) and amplitude (B) in NMJ preparations from control (black), Dscam2^null (red), Dscam2A (blue), and Dscam2B (magenta; one-way ANOVA, all groups compared with Tukey’s post-test). (C) Representative traces of intracellular mEJP recordings. (D) Quantification of the amplitude of evoked potentials (EJP’; one-way ANOVA; all groups compared with Tukey’s post-test). (E) Representative traces of evoked EJP recordings. (F) Quantification of quantal content, the number of synaptic vesicles released following an evoked EJP’, which is calculated by dividing evoked EJP’ by single quanta (mEJP; one-way ANOVA; all groups compared with Tukey’s post-test). (G) Quantification of PPR across 20-ms, 50-ms, and 200-ms interstimulus intervals (n = 9–10; two-way ANOVA; groups within interstimulus interval compared with Tukey’s post-test). (H–J) Knockdown of Dscam2 in neurons and muscle. Quantification of EJP’ amplitude (H), mEJP amplitude (I), and quantal content (J). UAS-Dscam2-RNAi was driven by no Gal4 (control) or the following Gal4 lines: elav (all neurons), nSyb (all neurons), OK6 (motor neurons), OK371 (MNs), and BG487 (muscle; one-way ANOVA; groups compared with Tukey’s post-test). Data shown as mean ± SEM; n indicated in graph. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001 for all panels.