MAPT and Alzheimer disease: Next, to determine whether tau phosphorylation may contribute to 3xTg-AD mice not being able to complete the IntelliCage tasks, we performed western blots (Figure 6E) for serine (Ser) and threonine (Thr) tau phosphorylation sites Ser202/Thr205 (AT8) and Thr212/Ser214 (AT100); AT8 and AT100 are detectable via western blot by 6 months of age in 3xTg-AD mice (Oh et al., 2010; Parachikova et al., 2010).