Acetylates soluble but not nucleosomal histone H4 at 'Lys-5' (H4K5ac) and 'Lys-12' (H4K12ac) and, to a lesser extent, acetylates histone H2A at 'Lys-5' (H2AK5ac). Has intrinsic substrate specificity that modifies lysine in recognition sequence GXGKXG. May be involved in nucleosome assembly during DNA replication and repair as part of the histone H3.1 and H3.3 complexes. May play a role in DNA repair in response to free radical damage.
Specificity
Natural and recombinant Human Histone acetyltransferase type B catalytic subunit
Subcellular Location
Isoform B Cytoplasm Nucleus Nucleus matrix Nucleus nucleoplasm Localization is predominantly nuclear in normal cells. Treatment with hydrogen peroxide or ionizing radiation enhances nuclear localization through redistribution of existing protein.
Catalytic subunit of the type B histone acetlytransferase (HAT) complex, composed of RBBP7 and HAT1. Interacts with histones H4 and H2A. The interaction is dependent of the ability of RBBP7 to bind to the N-terminus of histones. Component of the histone H3.1 and H3.3 complexes.