Fig. 4: Exocytic machinery is unaltered in the chromaffin cells without endophilin.

a, b Confocal images of endophilin TKO and control (WT and littermate endophilin KOWTKO) chromaffin cells stained for chromogranin-A (CgA; LDCV marker) revealed no difference in the number of CgA-positive vesicles measured in the whole volume of the cell (N = 4, WT 5 mice (54 cells), KOWTKO 4 mice (42 cells), and TKO 5 mice (57 cells), p-value = 0.96, one-way ANOVA with Tukey’s multiple comparison). An optical section through the equatorial plane of the cells is shown in a. Scale bar 3 µm. c Images of endophilin TKO, littermate KOWTKO and WT chromaffin cells stained with anti-synaptotagmin-1 (Syt-1) and CgA antibodies. Scale bar 3 µm. d Immunofluorescence levels revealed no change in synaptotagmin-1 levels (N = 4, WT 5 mice (48 cells) and TKO 5 mice (67cells), p-value = 0.45, unpaired two-sided t-test). e Quantification of the Syt-1 intensity on the CgA-positive vesicles revealed no significant difference between the genotypes (N = 4, WT 4 mice (39 cells) and TKO 3 mice (23 cells), p-value = 0.76, unpaired two-sided t-test). f Representative images of endophilin TKO and WT chromaffin cell stained for Munc18-1, SNARE proteins SNAP25 and VAMP2 and synaptotagmin-7. g Quantification of Munc18-1 (N = 3, WT 3 mice (24 cells) and TKO 3 mice (22 cells), p-value = 0.25), SNAP-25 (N = 3, WT 3 mice (32 cells) and TKO 3 mice (35 cells), p-value = 0.07), VAMP2 (N = 3, WT 4 mice (43 cells) and TKO 4 mice (43 cells), p-value = 0.27) and Syt7 (N = 3, WT 3 mice (44 cells) and TKO 3 mice (42 cells), p-value = 0.082) immunofluorescence showed no significant changes for any of these proteins. Error bars denote SEM. N = number of independent replicates. ns not significant.