Histone acetylation is highly regulated by two families of enzymes: HATs, as mentioned earlier, and histone deacetylases (HDACs). HATs catalyze the transfer of acetyl groups from acetylCoA to a specific lysine residue, while HDACs catalyze the removal of acetyl groups from histones to yield free acetic acid (HDACs 1-11) or nicotinamide and 2′-O-acetyl-ADP-ribose (SIRT1-7) (Figure 1).
