Reversible acetylation of highly conserved lysine residues within the N-terminal tail domains of core histones, plays an important role in transcriptional regulation, cell cycle progression and developmental events. Histone acetylation is a dynamic process determined by the net activities of histone acetyltransferases (HATs) and the competing enzymes histone deacetylases (HDACs). Histone deacetylases activities are often, but not always, associated with transcriptional repression and nucleosomal condensations. Recruitment of the multiprotein complexes to promoter sites occurs by many sequence specific DNA-binding proteins such as unliganded nuclear hormone receptors, DP1-E2F, YY1 and Rb family of transcription factors, transcriptional repressors and tumor suppressors (e.g. BRCA1). Aberrant recruitment of HDACs by certain oncoproteins may occur in certain neoplastic diseases.
