HDAC6 and early-onset autosomal dominant Alzheimer disease: Since these increased acetylated tubulin levels do not correlate with the amounts of HDAC6 or αTAT1, it has been proposed that the reduced MT dynamics associated with impaired tubulin re-tyrosination, which is defective in Alzheimer’s disease, may upregulate the levels of acetylated tubulin, irrespective of the levels of the enzymes regulating tubulin acetylation.