Fig. 5: Surface interaction with D1R shapes GluN1 nano-organization and clustering.

a Representative image of hippocampal dendrites on which surface GluN1-NMDAR (green) and D1R (magenta) were labeled from D1R-wt, D1R-S397D (grey), or D1R-dT2 (orange) expressing neurons from 3 independent experiments. Scale bar, 2 µm. b Correlation between the size of GluN1-NMDAR cluster and the overlap between GluN1-NMDAR and D1R when co-expressed with D1R-wt, D1R-S397D or D1R-dT2. P-value were calculated using a two-sided t-test. c Example of diffraction-limited and super-resolution images of surface GluN1-NMDAR. Scale bar, 300 nm. d Representative images of super-resolved surface GluN1-NMDAR and diffraction-limited Homer 1 C staining. Scale bar, 1 µm. c, d Representative images from 4 independent experiments. e Representative clustering images obtained with SR-Tesseler software. Scale bar, 100 nm. f Comparison of the density of localizations per nanodomains inside and outside synapses when GluN1 is co-transfected with either D1R-WT (n = 7 cells), D1R-dT2 (n = 7) or D1R-S397D (n = 6; two-tailed Mann-Whitney U test). Data are presented as mean +/- SEM. g Representative immunofluorescence image of surface D1R (magenta) and Homer 1 C (green) from 3 independent experiments. Scale bar, 10 and 5 µm. h Cumulative distribution of the area in nm² of extra-synaptic GluN1-NMDAR nanodomains synapses when GluN1 is co-transfected with either D1R-WT (n = 88 nanodomains), D1R-dT2 (n = 136 nanodomains) or D1R-S397D (n = 102 nanodomains; two-tailed Kolmogorov-Smirnov test). Bar graphs represent mean +/- SEM. i Representative GCaMP6f-fluorescence images from 3 independent experiments. Scale bar, 2 µm. j Representative NMDAR-mediated Ca²⁺ signals, scale is 0.05 (D1R-WT and -dT2) or 0.2 (D1R-397D) ΔF/F. k Comparison of the NMDAR-mediated Ca²⁺-transient frequency in protrusions and dendrite when GluN1 is expressed together with D1R-wt (n = 153 spines and 54 shaft), D1R-S397D (n = 145 spines, 56 shafts) or D1R-dT2 (n = 105 spines, 45 shafts; two-tailed Mann–Whitney U test). Data are presented as mean +/- SEM. Source data are provided as a Source Data file.