Histone deacetylase complex subunit Sin 3a, Paired amphipathic helix protein Sin 3a, SIN3 homolog A,
Acts as a transcriptional repressor. Interacts with MXI1 to repress MYC responsive genes and antagonize MYC oncogenic activities. Also interacts with MAD-MAX heterodimers by binding to MAD. The heterodimer then represses transcription by tethering SIN3A to DNA. Acts as a corepressor for REST.