Methyltransferase enzyme

Methyltransferases are a large family of enzymes that catalyze the transfer of a methyl group from a donor molecule—most commonly S-Adenosylmethionine—to substrates including nucleic acids, proteins, lipids, and small molecules. This process is fundamental for epigenetic regulation, affecting gene expression without altering the underlying genetic code. Key subclasses include DNA methyltransferases—which add a methyl group primarily at cytosine bases in CpG dinucleotides—and histone/protein methyltransferases, which modify lysine or arginine residues on histones or other proteins. These modifications play critical roles in development, cell differentiation, X-chromosome inactivation, imprinting phenomena, chromatin structure maintenance, and protection against transposable elements. Dysregulation or mutation within specific members can contribute to cancer progression through inappropriate gene silencing/activation as well as other diseases such as neurodevelopmental disorders and metabolic syndromes.[1][2][3] The term “methyltransferase enzyme system” is not specific enough for structured drug discovery purposes; it encompasses many distinct targets with unique biological roles.[1]

Other names

MethyltransferaseMTaseDNA methyltransferase (for DNA-specific forms)Histone methyltransferase (for histone-specific forms)Protein methyltransferaseO-methyltransferases

Inhibition of enzymatic transfer of the methyl group from S-Adenosylmethionine to substrate molecules such as cytosines in DNA or lysines/arginines in proteins, leading to hypomethylation and reactivation of silenced genes or altered protein function