Figure 6: AMPAR EPSCs upon endogenous AMPAR replacement with tethered GluA1-γ−8.
A: Sedimentation experiments showing that, in contrast to WT TARP γ−8_CT, no LLPS were observed when mixing 60 μM mutant forms TARP γ−8_CT and 20 μM PSD-95. The quantification results were from 3 independent batches of sedimentation experiments and represented as mean ± SD.
B: Table listing the ITC-measured binding affinities between PSD-95 and different forms of TARP γ−8_CT. The raw data are shown in Figure S5A.
C: Schematic diagram showing the topology of the tethered GluA1-γ−8.
D: Scheme of the AMPAR replacement with tethered GluA1-γ−8 and timeline of the experiment.
E: Scheme of simultaneous dual whole-cell recording in the hippocampus.
F-J: Scatterplots of AMPAR EPSC for single pairs (open circles) of control and GluA1-γ−8_WT (F, n = 19 pairs), GluA1-γ−8_Δ4 (G, n =13 pairs), GluA1-γ−8_R8A (H, n = 13 pairs), GluA1-γ−8_S10D (I, n = 14 pairs) or GluA1-γ−8_φ123S (J, n = 15 pairs). Filled circles represent mean ± SEM. Insets show sample current traces from control (black) and transfected (green) neurons. Scale bars: 50 pA, 50 ms.
K: Summary plot comparing the log10 of the transfected/control neuron AMPAR EPSC ratio in all conditions tested.
L: Endogenous AMPAR replacement with recombinant GluA1-γ−8 constructs resulted in rectified synaptic AMPAR currents (n = 13 control and 8 transfected cells). Statistical significance was analyzed using the Wilcoxon signed-rank test in F-J and Mann–Whitney U test in L. One way ANOVA with Bonferroni multiple comparison test was used to compare relevant groups in K. * p < 0.05, ** p < 0.01, and *** p < 0.001 vs. control condition. # p < 0.05 vs. GluA1-γ−8_Δ4 condition. See also Figures S5–S6