Fig. 6: Synj1’s 5’-phosphatase domain is essential for the maintenance of basal-level surface DAT.

a Synj1 domain structure and mutations examined in this study. The R258Q and R839C mutations were associated with PD. The D730A mutation completely abolishes the 5’-PPase activity. b Representative images of N2a cells co-transfected with DAT-pHluorin and different variants of SYNJ1 immunolabeled by anti-GFP (green) and anti-Synj1 (red). c and d Analysis of DAT surface fraction (c) and vesicular pH (d) for DAT-pHluorin expressing N2a cells. The n = cell number was from three independent batches of cultures. e Representative images of N2a cells transfected with RFP-DAT (red) or co-transfected with RFP-DAT (red) and different variants of eGFP-SYNJ1 (green). f 2-dimensional distribution of surface RFP/intracellular RFP (sDAT/iDAT) and normalized GFP fluorescence for all cells. n from 2 to 3 independent batches of cultures. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. p values are from Mann–Whitney tests or Dunn’s post hoc tests following Kruskal–Wallis ANOVA.