MAPT and Parkinson disease: We have previously demonstrated the hyperphosphorylation of Tau in vivo in the MPTP-induced neurotoxin mouse model of parkinsonism [24], [27] and in vitro in MPP+-treated primary mesencephalic neurons [26], in SH-SY5Y neuronal cells [24]–[25], as well as in postmortem PD brains [23].