HDAC3 (Histone deacetylase 3) is a histone deacetylase protein. Histones play a critical role in transcriptional regulation, cell cycle progression and developmental events. Histone acetylation/deacetylation alters chromosome structure and affects transcription factor access to DNA. HDAC3 belongs to the histone deacetylase/acuc/apha family. It has histone deacetylase activity and represses transcription when tethered to a promoter. It may participate in the regulation of transcription through its binding with the zinc-finger transcription factor YY1. This protein can also down-regulate p53 function and thus modulate cell growth and apoptosis. This gene is regarded as a potential tumor suppressor gene.