The role of DNA methyltransferase 1 in growth control.

Vertebrate DNA contains in addition to the four bases comprising the genetic information a modified base, 5-methyl cytosine that plays an important role in the epigenome. The methylated bases form a pattern of methylation that is cell specific and is faithfully inherited during cell division. The enzyme DNA methyltransferase 1 DNMT1 is responsible for copying the DNA methylation pattern but other de novo methyltransferase as well as demethylases might also be involved. Multiple mechanisms are in place to ensure the coordinate inheritance of the DNA methylation pattern with DNA replication. There is a bilateral relationship between the cell cycle and DNMT1. The expression of DNMT1 is tightly regulated with the cell cycle while the expression of DNMT1 can affect the cell cycle. DNMT1 protein might regulate cell cycle events by mechanisms that are independent of its DNA methylation activity through its multiple protein-protein interactions. The unique position of DNMT1 in the cell cycle is consistent with the hypothesis that it plays an important role in cancer.