Ubiquitination was, however, studied in cells from Alzheimer’s disease (AD) patients, where it was shown to be greatly affected by changes in activities of multiple ubiquitinases and de-ubiquitinases, summarily leading to accumulation of such pathological peptides/proteins, such as amyloid-beta, phospho-Tau, and alpha-synuclein [126]. Here, MAPT is linked to Alzheimer disease.