HDT1 (HD2A) is probably mediating in the deacetylation of lysine residues on the N-terminal part of the core histones (H2A, H2B, H3 and H4). Histone deacetylation gives a tag for epigenetic repression and plays an important role in cell cycle progression, transcriptional regulation and developmental events. This protein is also involved in rRNA gene silencing in nucleolar dominance. Synonymes:HD-tuins protein 1, Histone deacetylase 2a.