Histone deacetylase 4 (HDAC4) is a zinc-dependent metalloenzyme and class IIa HDAC. It is composed of an N-terminal regulatory domain, which contains a myocyte-specific enhancer factor 2 (MEF2) binding site, three 14-3-3 binding sites, a nuclear localization signal, and a caspase-3 cleavage site, a catalytic domain,...