Inhibition of DNA methyltransferase inhibits DNA replication.
Ectopic expression of DNA methyltransferase transforms vertebrate cells, and inhibition of DNA methyltransferase reverses the transformed phenotype by an unknown mechanism. We tested the hypothesis that the presence of an active DNA methyltransferase is required for DNA replication in human non-small cell lung carcinoma A549 cells. We show that the inhibition of DNA methyltransferase by two novel mechanisms negatively affects DNA synthesis and progression through the cell cycle. Competitive polymerase chain reaction of newly synthesized DNA shows decreased origin activity at three previously characterized origins of replication following DNA methyltransferase inhibition. We suggest that the requirement of an active DNA methyltransferase for the functioning of the replication machinery has evolved to coordinate DNA replication and inheritance of the DNA methylation pattern.
Knox
J D
JD
Department of Pharmacology and Therapeutics, the McGill Cancer Centre, McGill University, 3655 Sir William Osler Promenade, Montreal, Quebec H3G 1Y6, Canada.
Araujo
F D
FD
Bigey
P
P
Slack
A D
AD
Price
G B
GB
Zannis-Hadjopoulos
M
M
Szyf
M
M
D000818:Animals; D002455:Cell Division; D002460:Cell Line; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000037:antagonists & inhibitors* / Q000235:genetics; D004261:DNA Replication; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology; D016133:Polymerase Chain Reaction
D004791:Enzyme Inhibitors; D020319:Oligodeoxyribonucleotides, Antisense; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases