DNA methyltransferase

Function DNA methyltransferase (DNMT) catalyzes the transfer of methyl group to DNA. Methylation is essential for gene expression. DNMT uses S-adenosyl methionine (SAM) as the methyl donor. The SAM analog S-adenosyl homocysteine (SAH) is a powerful inhibitor of DNMT. Methylguanine DNMT repairs the DNA lesion O6-methylguanine to guanine. Methylcytosine DNMT methylates the 5 position of cytosine. Methyladenine DNMT methylates the 6 position of adenine. HhaI DNA methyltransferase (HDMT), a DNMT from Haemophilus haemolyticus recognizes the 5’-GCGC-3’ DNA sequence and methylates the first cytosine to convert it to 5-methylcytosine. The SAM serves as the methyl donor in the reaction and is converted to to S-adenosyl-L-homocysteine (SAH) by the reaction. Relevance DNMT inhibitors are being tested in cancer therapy. Disease The human ICF disorder is caused by mutations in DNMT 3B. Structural highlights The . 3D Structures of DNA methyltransferase DNA methyltransferase 3D structures

spinqualitylabelsall models Adenine DNMT complex with SAM and Cl- ion (PDB code 1nw5). Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image