Figure 2. Nanodomain-localized DAT is preferentially in an inward-facing conformation.

(A–D) dSTORM on DA neurons and DAT-expressing CAD cells labeled with the fluorescent cocaine analog DG3–63 (10 nM).
(A) Axonal extension.
(B) Varicosity (box in A).
(C) CAD cell.
(D) ROI from (C).
(E–H) The density-based association of DG3–63 with mEOS2-DAT.
(E) Cartoon of the labeling strategy.
(F) dSTORM/PALM image of a CAD cell expressing mEOS2-DAT (red) and labeled with DG3–63 (10 nM) (blue).
(G) Close up dSTORM/PALM image of CAD cell expressing mEOS2-DAT (red) and labeled with DG3–63 (10 nM) (blue).
(H) The DG3–63 signal is blocked by 100 μM cocaine.
(I–L) Voronoi tessellation-based colocalization algorithm. Tessellation is performed on the mEOS2-DAT data, and areas are marked when the mEOS2-DAT localization has a DG3–63 localization within 25 nm.
(L) Left: total mEos2-DAT Voronoi tesselated area distribution (red) (probability density function [PDF]) and tessellated areas of mEos2-DAT associated with DG3–63 (blue). Right: tessellated areas for mEos2-DAT associated with DG3–63 (blue) compared with that associated in the presence of saturating cocaine.
(M–O) Total internal reflection fluorescence (TIRF)/dSTORM of WT DAT and the inward-facing mutant (D421N) expressed in CAD cells.
(M) Example image of DAT expressed in CAD cells.
(N) Example images of DAT clusters identified by DBSCAN in WT DAT and D421N D expressing cells; clusters with diameter >75 nm in green, clusters <75 nm in magenta.
(O) Normalized fraction of clusters with a diameter greater than 75 nm (percent). Means ± S.E. from 38 WT DAT cells and 42 D421N cells, 3 transfections, ***p < 0.001, unpaired t test.
(P–R) dSTORM of WT DAT and the inward-facing mutant (D421N) expressed in CAD cells.
(P) Number of localizations per square meter for WT DAT and D421N. Means ± S.E., unpaired t test, p = 0.4.
(Q) Example images of DAT clusters identified by DBSCAN in WT DAT and D421N D expressing cells; dense clusters (>80 localizations within a radius of 50 nm) in red.
(R) Fraction of localizations in dense clusters (in percent of WT DAT). Means ± S.E. from 38 WT DAT cells and 42 D421N cells, 3 transfections, **p < 0.01, unpaired t test.
See also Figure S3.