MAPT and Alzheimer disease: We have previously described how the linear AChE-peptide may contribute to events underlying neurodegeneration, since (1) is elevated in AD brains (Garcia-Ratés et al., 2016), (2) alters the expression pattern of α7-nAChR, APP, Aβ, p-Tau, and GSK3 (Bond et al., 2009; Garcia-Ratés et al., 2016; Brai et al., 2017), (3) affects calcium influx (Bon and Greenfield, 2003; Greenfield et al., 2004), cell viability (Day and Greenfield, 2003) and AChE release (Day and Greenfield, 2003; Garcia-Ratés et al., 2016), and (4) modulates neuronal activity (Badin et al., 2013, 2016).