Sin3A Associated Protein 30kDa (SAP30)

SAP30 binds to the transcriptional corepressor mSin3 and is capable of mediating transcriptional repression via histone deacetylases. SAP30 also binds the N-CoR corepressor and is required for N-CoR-mediated repression by antagonist-bound estrogen receptor and the homeodomain protein Rpx, as well as N-CoR suppression of transactivation by the POU domain protein Pit1.

The human SAP30 protein contains 220 amino acids. the human SAP30 complex is active in deacetylating core histone octamers, but inactive in deacetylating nucleosomal histones due to the inability of the histone-binding proteins RBBP7 and RBBP4 to gain access to nucleosomal histones.