Fig. 5

Tau mutations that modulate interactions between tau and Fyn. a Diagram indicating deletion and point mutations in 0N4R mTau and corresponding residues in 2N4R hTau in parentheses. Epitopes of the Tau1 and Tau5 antibodies are indicated also. b Interactions between Fyn and exogenous tau in transfected Mapt ^−/− neurons were determined by proximity ligation assay (PLA) using the Fyn3 antibody in combination with the Tau5 (left) or Tau1 (right) antibodies. Tau5 detects total tau, whereas Tau1 detects tau that is unphosphorylated at residues S198, S199 and S202. The closeness of interactions between Fyn and tau was expressed relative to measurements obtained in Mapt ^−/− neurons transfected with GFP-P2A-mTau^WT (WT). The other cultures were transfected with similar constructs in which mTau^WT was replaced by the indicated tau mutants. n = 16–31 neurons per construct from two experiments (three different neurites were quantified and averaged per individual transfected neuron). c The abundance of tau in transfected (GFP-positive) Mapt ^−/− neurons was estimated based on relative immunofluorescence intensities detected after staining of cultures with Tau5 (left) or Tau1 (right) and normalization to GFP signals. Average levels in GFP-P2A-mTau^WT (WT)-transfected cultures were arbitrarily defined as 1.0. *P < 0.05, **P < 0.01, ****P < 0.0001 vs. WT by one-way ANOVA and Bonferroni test. Data are means ± SEM