4da4 | pdb_00004da4
Structure of mouse DNMT1 (731-1602) bound to hemimethylated CpG DNA
Structural highlights
Function[DNMT1_MOUSE] Methylates CpG residues. Preferentially methylates hemimethylated DNA. Associates with DNA replication sites in S phase maintaining the methylation pattern in the newly synthesized strand, that is essential for epigenetic inheritance. Associates with chromatin during G2 and M phases to maintain DNA methylation independently of replication. It is responsible for maintaining methylation patterns established in development. DNA methylation is coordinated with methylation of histones. Mediates transcriptional repression by direct binding to HDAC2. In association with DNMT3B and via the recruitment of CTCFL/BORIS, involved in activation of BAG1 gene expression by modulating dimethylation of promoter histone H3 at H3K4 and H3K9.[1] [2] [3] Publication Abstract from PubMedDNMT1, the major maintenance DNA methyltransferase in animals, helps to regulate gene expression, genome imprinting, and X-chromosome inactivation. We report on the crystal structure of a productive covalent mouse DNMT1(731-1602)-DNA complex containing a central hemimethylated CpG site. The methyl group of methylcytosine is positioned within a shallow hydrophobic concave surface, whereas the cytosine on the target strand is looped out and covalently anchored within the catalytic pocket. The DNA is distorted at the hemimethylated CpG step, with side chains from catalytic and recognition loops inserting through both grooves to fill an intercalation-type cavity associated with a dual base flip-out on partner strands. Structural and biochemical data establish how a combination of active and autoinhibitory mechanisms ensures the high fidelity of DNMT1-mediated maintenance DNA methylation. Structure-based mechanistic insights into DNMT1-mediated maintenance DNA methylation.,Song J, Teplova M, Ishibe-Murakami S, Patel DJ Science. 2012 Feb 10;335(6069):709-12. PMID:22323818[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||||||
