MAPT and Alzheimer disease: This six ring π-stack at the interprotofilament interface is also different from the interfaces found in other fibrils, which involve steric zippers (α-synuclein12,13 and Aβ40/Aβ4210), and backbone hydrogen bonding or coordination of the disordered terminus in different polymorphs of Tau in Alzheimer’s disease (Supplementary Table 7)11.