Devoided of intrinsic deacetylase activity, promotes the deacetylation of lysine residues on the N-terminal part of the core histones (H2A, H2B, H3 and H4) by recruiting HDAC1 and HDAC3. Histone deacetylation gives a tag for epigenetic repression and plays an important role in transcriptional regulation, cell cycle progression and developmental events. Represses MEF2-dependent transcription, inhibits skeletal myogenesis and may be involved in heart development. Protects neurons from apoptosis, both by inhibiting JUN phosphorylation by MAPK10 and by repressing JUN transcription via HDAC1 recruitment to JUN promoter.