Iron plays a role in methylation, a process by which methyl groups are added to DNA, RNA, and proteins. This process can affect the expression of genes.
Iron is a cofactor for several enzymes involved in methylation reactions, including the enzymes that catalyze the formation of S-adenosylmethionine (SAM), the main methyl donor in the cell, and the enzymes that catalyze the conversion of homocysteine to methionine, which is also an important step in the methylation cycle.
Additionally, iron can also act as a mediator of epigenetic modifications, by affecting the activity of enzymes that catalyze the methylation and demethylation of DNA, such as histone deacetylases (HDACs) and TET enzymes.
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