Tau seeds can also cause toxicity and cell death via Ca2+ dysregulation (Querfurth and LaFerla, 2010; Tian H. et al., 2013; Hallinan et al., 2019); altered intracellular Ca2+ homeostasis results in tau phosphorylation, which is related to tau pathology progression in AD (Delacourte et al., 1999). Here, MAPT is linked to Alzheimer disease.