Related Resources: Brochures | Application NotesThe addition of methyl groups to cytosine residues in DNA is an epigenetic regulatory strategy used by eukaryotic genomes to modulate the expression of genes. It is well established cytosine methylation is involved in the regulation of many cellular processes, including chromosome stability, X chromosome inactivation, embryonic development, and genomic imprinting. Consequently the methylation of DNA in a location and temporal specific fashion plays an essential role in gene silencing in embryonic development, and inactivation of defined tumor suppressor genes in human cancers.
About 1% of the genome consists of 500-2000 bp CpG-rich areas or islands. About half of all CpG islands correspond to transcription start sites and promoters of expressed genes. In active genes these regions tend to be unmethylated. In diseases such as cancer these regions can become hyper methylated resulting in abnormal silencing of a specific gene. While methylation of promoter regions is correlated with gene repression, methylation of the gene body is correlated with expression.
DNA methylation occurs mainly at the 5’ position of cytosine bases and is mediated by enzymes called DNA methyltransferases (DNMT). 5-methylcytosine can be further modified to 5-hydroxymethylcytosine (5-hmC) by the family of Ten-Eleven Translocation (TET1-3) enzymes. These enzymes appear to convert a methylated cytosine to an unmethylated cytosine by converting 5-hmC to 5-formylcytosine (5fC), then 5-carboxylcytosine (5caC). In this process 5fC and 5caC can be converted to an unmodified cytosine by Terminal deoxynucleotidyl transferase (TdT). The 5hmC and TET enzymes may be involved in tumorigenesis, and are therefore key targets for epigenetics research, to fully elucidate the dynamic changes in the epigenome involved in development and disease.
Regions of methylated DNA can be bound by a variety of methylated DNA binding proteins (MBD). The presence or absence of these proteins is believed to resulting recruitment of specific histones and other chromatin associated proteins to either activate or repress gene expression.
DNA Methylation Applications
Merck offers a wide selection of antibodies with proven performance in DNA methylation specific applications such as methylated DNA immunoprecipitation (meDIP) and MBD pulldown, as well as standard applications such as Western Blotting and immunoprecipitation. Use the table below to browse our selection of antibodies or use our antibody search tool to find the exact antibody you need.
Looking for products for bisulfite modification, methylation specific PCR, or DNA methylation standards and controls? Please visit our DNA Methylation Assays page.
Featured Antibody: Anti-DNMT3A2
Staining of NIH/3T3 cells using Anti-DNMT3A2 (Cat No. 07-2050, red). Actin filaments have been labeled with Alexa Fluor 488-Phalloidin (green). This antibody positively stains the nucleus.
Featured Antibody: Anti-DMAP1, CT
Staining of HeLa cells using Anti-DMAP1, CT (Cat. No. 07-2072, red). Actin filaments have been labeled with AlexaFluor®488-Phalloidin (green). Nuclei are stained with DAPI (blue). This antibody positively stains the nucleus.