MAPT and Alzheimer disease: Moreover, GSK3β is the first identified tau kinase and participates in both tau and amyloid pathologies in AD, which is also regarded as a molecular link between the two major histopathological hallmarks of the disease (Avila, Wandosell, & Hernandez, 2010; Ishiguro, Omori, et al., 1992; Ishiguro, Takamatsu, et al., 1992).