Selective inhibition of cytosine-DNA methylases by polyamines.
We have advanced the hypothesis that polyamines affect DNA methylation and thus promote the expression of developmentally controlled genes. We demonstrate that the activity of cytosine-DNA methyltransferases HpaII, HhaI, HaeIII and SssI is inhibited by physiological concentrations of polyamines. On the other hand, activity of the adenine-DNA methyltransferase EcoRI, and restriction enzymes HpaII, HhaI, HaeIII and EcoRI, is insensitive to polyamine concentrations up to 40 mM. Our results indicate that the effect of polyamines on cytosine-DNA methyltransferases is rather selective and suggest a possible mode of action in vivo.
Ruiz-Herrera
J
J
Departmento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Gto., Mexico.
Ruiz-Medrano
R
R
Domínguez
A
A
D004247:DNA / Q000378:metabolism; D015257:DNA-Cytosine Methylases / Q000037:antagonists & inhibitors*; D008745:Methylation; D011073:Polyamines / Q000494:pharmacology*; D013095:Spermidine / Q000494:pharmacology
D011073:Polyamines; D004247:DNA; D015257:DNA-Cytosine Methylases; D013095:Spermidine