DMAP1 Antibody #13326

DNA methyltransferase 1 (DNMT1)-associated protein 1 (DMAP1) is a nuclear protein that functions in transcriptional repression and DNA repair. DMAP1 was first identified as an activator of DNMT1 methyltransferase activity (1). Both DMAP1 and DNMT1 are targeted to replication foci during S phase and function to transfer proper methylation patterns to newly synthesized DNA during replication (1). In late S phase, DMAP1-DNMT1 co-operate with a p33ING1-Sin3-HDAC2 complex to maintain pericentric heterochromatin by deacetylating histones, methylating histone H3 at Lys9, and methylating DNA (1,2). The DMAP1 protein is also part of the TIP60-p400 complex, a histone acetyltransferases (HAT) and chromatin-remodeling complex that functions in DNA repair (3,4). Upon DNA damage, the TIP60-p400 complex acetylates histone H4 at Lys16 to induce chromatin relaxation and activation of the ATM kinase. DMAP1 is required for DNA-damage induced TIP60-p400-mediated histone acetylation, and deletion of DMAP1 impairs AMT function (5). DMAP1-DNMT1 may also methylate DNA at sites of DNA damage during homologous recombination, which results in gene silencing (6).