Fig. 3.

VPS50 KO neurons show a reduction in synaptic activity that can be recovered by inducing synaptic vesicle acidification. Cortical neuronal cultures from Cas9KI animals were transduced at 3DIV and at 12–13 DIV used for electrophysiology or calcium imaging. A Representative traces and B, C quantification of amplitude (B) and frequency (C) of spontaneous AMPA-mediated EPSCs. D Representative traces and E, F quantification of the frequency (E) and amplitude (F) of miniature AMPA-mediated currents. G Representative traces and quantification of the frequency (H) of current clamp recordings of control and VPS50 KO neurons. I–K Representative traces of current clamp recordings of control and VPS50 KO neurons expressing pHoenix. Orange bars under the traces show the periods pHoenix was activated. K Quantification of the frequency of spiking of control and VPS50 KO neurons before, during, and after stimulus with pHoenix to artificially acidify synaptic vesicles. For all experiments, at least 18 neurons from 3 independent experiments were analyzed. Unpaired t-test was used for statistical analysis; ***p < 0.001. Error bars represent mean ± SEM