MAPT and Alzheimer disease: The PTMs (Ub-K311, Ub-K317, and Ub-K267 + P-S262) in soluble tau from postmortem human brains have been identified as AD-specific, distinguishing them from other tauopathies, such as CBD, FTD, and PiD (Kyalu Ngoie Zola et al., 2023).