FIGURE 1.

Extracellular tau3RC peptide promotes endogenous tau phosphorylation. A and B, representative images of SH-SY5Y human neuroblastoma cells treated for 48 h with vehicle solution (A) or with 1 μm tau3RC peptide (B) are shown. Scale bar, 50 μm. A clear morphological change was found upon tau peptide addition. C, cellular extracts from SH-SY5Y stimulated with vehicle (Vh) or with tau3RC (3RC; 1 μm for 48 h) were analyzed by Western blotting using Tau-1 antibody. Protein bands were scanned and normalized to Tau-5 level. 100% corresponds with the ratio tau-1/tau-5 obtained in vehicle-treated SH-SY5Y cells. Graph represents the mean ± S.D. (error bars) from three individual experiments. *, p < 0.05.