Extended Data Fig. 4: Loss of AP-3 specifically impairs release at high frequency.
a, Hippocampal neurons from WT and mocha mice expressing VAMP7-pH were stimulated at 5, 10, 25 and 50 Hz for 60-150 s in the presence of 60 nM bafilomycin and the fluorescence response normalized as shown in Fig. 1 (above). Statistical analysis of the response at 4 s is shown below. 25 Hz: P = 6 × 10−15, 2 s; 1.22 × 10−12, 3 s; 9 × 10−14, 4 s. 50 Hz: P = 2.16 × 10−7, 1 s; 5.71 × 10−11, 2 s; 2.01 × 10−12, 3 s; 2.9 × 10−14, 4 s). n = 16/3. b, The initial rate of fluorescence increase per action potential in WT and mocha neurons: P = 0.029,10 Hz; 1.133 × 10−6, 25 Hz; 3.56 × 10−10, 50 Hz (n = 12/3). c, The proportion of VAMP7-pH that responds to stimulation (recycling pool size) in WT and mocha neurons: P = 0.0084, 10 Hz; 1.12 × 10−13, 25 Hz; 5.2 × 10−14, 50 Hz (n = 16/3). n = x/y where x is the number of fields examined and y the number of independent experiments. The data indicate mean ±  s.e.m. for individual coverslips containing 50-100 boutons each. *, P < 0.05; **, P < 0.01; ****, P < 0.0001 by two-way ANOVA with Tukey’s multiple comparisons test.
