Figure 2. The figure depicts transcriptional regulation of DNMT1 expression by different cellular signaling pathways. The expression and activity of DNMT1 is synchronized by a number of signal transduction pathways that include cancer prone cellular signaling pathways such as RAS and PI3K/PKB as well as developmentally inclined networks such as HH and TGFβ-SMAD pathways. These signaling pathways control the expression of DNMT1 and, consequently, the functioning of the DNA methylation machinery to maintain a homeostatic pattern of gene expression in accordance to the cellular needs. P1, P2, P3 and P4 represents the transcription initiation sites and AP1, AP2, AP3 represents the three AP (activator protein) sites. Blue dots downstream of P1 site represent the three c-Jun-dependent enhancers.