MAPT and Alzheimer disease: The autophagic-lysosomal pathway is another important Aβ clearance pathway, the in vivo function of which in AD pathology is revealed in Drosophila. The hyperactivated PI3K/AKT/mTOR pathway, a negative-regulating pathway against autophagy, is linked to disrupted clearance of Aβ and tau [61] and alterations in this pathway are associated with autophagic dysfunction in the AD brain [62].