Fig. 2.

Metabolic processes tightly intertwined with DNA methylation. The yellow pathway refers to the folate cycle which mainly takes place in the mitochondria, and generates methionine. The red cycle is the methionine cycle which is important for the production of SAM in the cytoplasm. The blue network represents DNA methylation, and highlights the modification that happens on the genome, for example, in the nucleus. The transsulfuration pathway shown in green involves the irreversible transformation of homocysteine, leading to gluconeogenesis which takes place in the mitochondria, cytosol and the endoplasmic reticulum