Fig.4.
Aβ binds and accumulates at both pre- and post-synaptic sites. A, B) Double-labeling with two different pre-synaptic and post-synaptic markers synapsin I and PSD-95 (A) and synaptophysin and drebrin (B), respectively, of primary neurons treated with 0.5 μM of fluorescently tagged Aβ1 - 42 for 30 min. In the colocalization channel (right panel) the amount of colocalization is represented as such as the brighter the pixels, the higher the colocalization at that particular pixel. Scale bars 50 μm. C, D) The scatter plots show the intensity of the Aβ1 - 42 channel plotted against the intensity of the respective pre- or post-synaptic channel for each pixel. Quantification shows no significant difference in the percentage of colocalization above threshold between Aβ555 and pre- or post-synaptic markers. E, F) Pearson’s correlation coefficient (PCC) values between PSD-95 and synapsin I, and drebrin and synaptophysin, respectively, are not significantly different. Manders’ Colocalization Coefficients (MCC) values for Aβ1 - 42 are also not significantly different between pre- and post-synaptic markers.