Methylation is a key process in one-carbon metabolism, a biochemical pathway that involves the transfer of one-carbon units between different compounds. One-carbon metabolism is critical for the synthesis of nucleotides, the building blocks of DNA and RNA, and for the regulation of gene expression.
In methylation, a methyl group (-CH3) is transferred from a donor molecule, such as S-adenosylmethionine (SAMe), to a target molecule, such as DNA, RNA, proteins, or lipids. This transfer is catalyzed by enzymes called methyltransferases, which are involved in a wide range of cellular processes, including metabolism, DNA repair, gene expression, and protein function.
Methylation is also involved in the recycling of homocysteine, an amino acid that can be harmful to cells if it accumulates in the body. Methylation helps convert homocysteine to methionine, which can be used to produce SAMe, the primary methyl donor in the body. An imbalance in methylation can have emotional, physical, and mental consequences.
In summary, some of the key roles of methylation include:
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Methylation balancing is unique to each person, but can be done through diet and lifestyle changes.