Hyperphosphorylated tau is neurotoxic (Kopeikina et al., 2012), and understanding the processes underlying its generation is of great importance, not only for the AD field, but also for other neurodegenerative diseases (tauopathies), in which aberrant tau phosphorylation plays a key role (Orr et al., 2017). Here, MAPT is linked to Alzheimer disease.