[Effect of sphingomyelin and its enzymatic hydrolysis products on heterologous methylation of calf thymus DNA by cytosine-DNA-methyltransferase EcoRII].

It was found that sphingomyelin and its enzymatic hydrolysis products, choline and sphingosine, influence the degree of DNA methylation in the reaction of heterologous methylation by methylase EcoRII in vitro. Sphingomyelin was found to be able to was activate (by 20%), sphingosine and choline inhibit methylation. Phosphatidylcholine had no effect on DNA methylation in an in vitro system. The role of lipids in the regulation of gene expression during enzymatic modification (methylation) of DNA is discussed.