(E) Partial overlap between the SSDs of GlyRs and GABAARs. The fraction of overlapping SSDs was calculated based on the binarized images for each synapse (without selection for synapse orientation), dividing the number of overlapping SSDs by the total number of SSDs for each receptor. Data are shown as median, 25% and 75% quartiles of the population (only synaptic clusters with ≥ 2 SSDs in the respective channel; n = 183 for GABAAR-A647, n = 277 for GlyR-Cy3B, from three independent experiments). GlyRs labelled with both Alexa 647- and Cy3B-conjugated secondary antibodies for the same primary antibody were used as positive control (n = 158 GlyR-A647 and n = 171 GlyR-Cy3B clusters from two independent experiments). The GABAAR-GlyR overlap is significantly lower than the GlyR-GlyR match (KW test, p < 0.0001). 