Importantly, it is possible that a direct interaction between the two proteins may be involved in the induction of synaptic dysfunction as tau and Aβ coexist within synaptic compartments in AD brain (Hoover et al., 2010; Ittner et al., 2010; Zempel et al., 2010; Tai et al., 2012; Miller et al., 2014). Here, MAPT is linked to Alzheimer disease.