MAPT and Alzheimer disease: In addition to glycogensynthase kinase 3 (GSK3), p38, and ERK,JNK phosphorylates Tau at various sites that are hyperphosphorylatedin paired helical filaments.17,18 Furthermore, JNK activityis enhanced in AD mouse models, in which JNK is co-localized withphosphorylated Tau.19,20 Notably, the JNK peptide inhibitor,D-JNKI-1, decreased Tau phosphorylation and subsequent aggregation.20