Additionally, Tau, a microtubule-associated protein present in axons and pre- and post-synaptic compartments, is hyperphosphorylated in AD, and tends to aggregate, forming toxic species that can propagate through synapses, impair axonal transport, and lead to the formation of NFTs (Wu et al., 2016; Gallardo and Holtzman, 2019; Knopman et al., 2021). Here, MAPT is linked to Alzheimer disease.