DYRK1A and Alzheimer disease: In AD, DYRK1A is especially known to phosphorylate Tau at several sites including Thr181, Thr212, and Thr231, which are all observed in NFTs of AD brains [29, 33, 46] and the amyloid precursor protein (APP) at Thr-668 [34] or the presenilin 1 (PS1) at Thr-354 [36].