Overexpression of hTau increases acetylated level of STAT1 by tau acetyltransferase activity. (A-C) Overexpression of hTau increased the acetylation of STAT1 level in whole cell extracts and the cytoplasm, while decreased acetylated STAT1 in the nuclear extracts. Proteins were first immunoprecipitated with STAT1, and then detected with anti-ace-lysine antibody in whole cell, cytoplasmic and nuclear extracts by Western blotting. (D, E) Overexpression of hTau increased the interaction of STAT1 and STAT3 in the cytoplasmic fraction in HEK293 cells measured by CO-IP. (F, G) STAT1KR (K410/K413R-STAT1) restored hTau induced-decreased STAT3 in the nuclear fraction (B) and had no effects in STAT3 levels in total extracts measured by Western blotting (A) and quantitative analysis (n = 3). Data were presented as mean ± SD. *, p < 0.05, **, p < 0.001, ***, p < 0.0001 vs Ctrl or hTau.