MAPT and Alzheimer disease: AD P-tau-induced hyperphosphorylation of tau at Ser202/Thr205 (AT8), Thr212, Ser214, Thr217, Ser262, and Ser422 (Figures 2A,B), suggesting that both proline-directed protein kinases (PDPKs) and non-PDPKs may participate in the hyperphosphorylation of tau in the AD P-tau injected mouse brains.