Probably mediates 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 transcriptional regulation, cell cycle progression and developmental events. Involved in the modulation of abscisic acid and stress-responsive genes. Interacts with DNMT2. Expressed in leaves, roots, stems, young plantlets, flowers and siliques. Highest levels in ovules, embryos, shoot apical meristems and first leaves. Also expressed in somatic embryos. Repressed by abscisic acid. Belongs to the histone deacetylase HD2 family.