title: Mechanism of CpG DNA methyltransferases M.SssI and Dnmt3a studied by DNA containing 2-aminopurine.
abstract: Murine DNA methyltransferases Dnmt3a-CD and M.SssI from Spiroplasma methylate cytosines at CpG sites. The role of 6-oxo groups of guanines in DNA methylation by these enzymes has been studied using DNA substrates, which contained 2-aminopurine at different positions. Removal of the 6-oxo group of the guanine located adjacent to the target cytosine in the CpG site dramatically reduces the stability of the methyltransferase-DNA complexes and leads to a significant decrease in the methylation. Apparently, O6 of this guanine is involved in the recognition of CpG sites by the enzymes. Cooperative binding of Dnmt3a-CD to 2-aminopurine-containing DNA and the formation of nonproductive enzyme-substrate complexes were observed.
authors: Department of Chemistry, Moscow State University, Moscow, Russia.
authors: Natalia A
authors: NA
authors: Cherepanova
authors: Antonio S
authors: AS
authors: Minero
authors: Alina R
authors: AR
authors: Rakhimova
authors: Elizaveta S
authors: ES
authors: Gromova
mesh_terms: D015075:2-Aminopurine / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D018899:CpG Islands; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D019175:DNA Methylation; D000090205:DNA Methyltransferase 3A; D015257:DNA-Cytosine Methylases / Q000378:metabolism*; D051379:Mice; D009691:Nucleic Acid Denaturation; D011485:Protein Binding; D013149:Spiroplasma / Q000201:enzymology*
chemical_list: C000715535:Dnmt3a protein, mouse; D015075:2-Aminopurine; D004247:DNA; C081573:DNA modification methylase SssI; D015257:DNA-Cytosine Methylases; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A