Fig. 3

Nlg1-Y782A but not –Y782F trap surface-diffusing AMPARs. a Neurons were live labeled for endogenous AMPARs with a GluA1 antibody mixed with Atto594-conjugated anti-rabbit Fab. The postsynaptic density (PSD) was detected with Homer1c-GFP. b Representative trajectories of individual AMPARs at the neuronal surface (red) in DIV 10 neurons expressing EV, Nlg1-WT, -Y782A, or -Y782F and Homer1c-GFP (white). Scale bar, 2 µm. c Average mean square displacement (MSD) and d distributions of individual diffusion coefficients in log scale from one experiment, for the four conditions (number of cells/number of trajectories, EV: 8/5690; Nlg1-WT: 7/4340; Nlg1-Y782A: 8/18059; Nlg1-Y782F: 8/16978). Note the higher MSDs and larger peaks of mobile receptors for EV and Nlg1-Y782F, compared to Nlg1-WT and -Y782A. The fraction of slowly mobile molecules on the left of the histogram (D < 0.01 µm² s⁻¹) is gray-shaded. e The median diffusion coefficient per cell was averaged for each condition (3 independent experiments). The number of cells examined is given in the columns. f Effect of the Nlg1 mutations on the number of Homer-1c puncta per unit length of dendrite (3 independent experiments). Data in graphs e and f represent mean ± SEM and were compared by a Kruskal–Wallis test followed by Dunn’s multiple comparison test (*P < 0.05, ***P < 0.001)