MAPT and Alzheimer disease: This should be of particular interest to AD researchers as mTOR signaling has also been implicated in learning and memory, and, more specifically, appears to have a bidirectional upregulatory relationship with Aβ, leading to an increase in hyperphosphorylation of Tau (Hoeffer et al., 2008; Oddo, 2012; Huang et al., 2013).