Figure 4.

Human tau pathology spreads from presynaptic terminals derived from neurons overexpressing tau to the postsynapses of the MML of the dentate gyrus. Human tau pathology is present within the MML of 3–6 month (A) 9 month (C) and 18 month old (E) rTgTauEC + EC‐tdTomato/Syp‐GFP mice. Individual postsynapses detected by PSD95 are Tau13 positive at 3–6 months (B) 9 months (D) and 18 months (F). Arrows depict postsynapses, arrowheads depict neighboring presynapses derived from neurons overexpressing tau. Array tomography quantification reveals a subset of postsynapses (G) and a subset of putative synaptic pairs (H) colocalize with Tau13 at 3–6, 9, and 18 months of age. Scale bars represent 20 μm in a, c, e, and 1 μm in B,D,F. Data shown are medians and interquartile ranges; individual points represent the median value from each mouse