The methylation status of the genome can be pharmacologically influenced using the anti-metabolite aza-cytidine or aza-deoxycytidine. These agents tend to deplete methylgroups from the epigenetic encryption system in animal cells and lead derepression of silenced genes [2-4]. The mechanism of action is based on the fact that these drugs trap catalytically active DNMTs on the genome and deplete the pool of methylases thereby leading to hypomethylation and reversal of silencing. Methylation, Ltd. is offering highly purified human DNA in two formats suitable for studies on methylase action in vitro: 1. A control DNA lacking aza-C (Catalog # HUDNA-B10 and HUDNA-B25) and; 2)Aza-C substituted human genomic DNA (Catalog # HUDNA-AZ10, HUDNA-AZ25). These DNAs are from HeLa cells and have been CsCl banded to give high purity DNA that is lightly sheared. The aza-C was incorporated in vitro and has not been exposed to DNMT isoform activity. The aza-C DNA will bind DNMT covalently in vitro.
Methylation, Ltd. has produced purified human DNA and azaC substituted DNA for research purposes only. These DNAs have been purified by proteinase K digestion and isopycnic banding. After recovery and dialysis, the DNA was labeled in vitro using DNA polymerase and either dCTP (control DNA) or aza-dCTP (aza-C DNA). DNAs were ethanol precipitated and resuspended in 10 mM Tris-HCl (pH 7.5), 1 mM EDTA at the concentration specified.
These DNAs are shipped on Dry Ice and should be stored at -20oC. Freezing/thawing cycles may shear the DNA but will otherwise not affect biological properties. The products are stable for 6 months after shipping.
This product is designed for research use only and not suitable nor approved for diagnostic procedures in animals or humans.
1. Robertson, K. D. (2001) Oncogene 20, 3139-355.
2. Costello, J. F., Plass , Christoph (2001) J Med Genet 38, 285-303.
3. Baylin, S., Esteller, M, Rountree, M, Bachman, K. Schuebel and Herman, G. (2001) Human Molecular Genetics 10, 687-692.
4. Liu et al., (2003) Molec. Cell. Biol. 23: 2709-2719.