Fig. 5.

VGAT immunoisolates are enriched for GABA uptake activity and impoverished for glutamate uptake activity. FCCP-sensitive GABA (A) and glutamate (B) uptake activities in LP2 (Input), unbound material (Sup), and bound material on VGAT beads (Beads) were measured using radiolabeled substrates and a standard filtration assay as described in Materials and Methods. All values were normalized to the relative amount of vesicle marker synaptophysin. The figures shows mean ± SD values of at least two independent experiments (in each experiment, n = 4).