Histone Deacetylase 6 (HDAC6) Is an Independent Deacetylase for α-Tubulin

Histone deacetylase 6 (HDAC6) is a cytosolic enzyme that catalyzes deacetylation of several proteins. Acetylated tubulin has been recently identified as a physiological substrate of HDAC6. However in previous reports, all in vitro binding and enzymatic assays were accomplished with only partially purified protein samples. Therefore, it still remained unclear whether HDAC6 alone could interact with tubulin and catalyze deacetylation. In this study, both binding and enzymatic assays were conducted using recombinant-derived HDAC6 and purified alpha/beta tubulin to eliminate possible contamination. The results clearly demonstrated that interaction between HDAC6 and tubulin is independent of other proteins. In addition, HDAC6 can independently catalyze deacetylation of both tubulin dimer and microtubule polymer.