A process by which methyl groups are added to DNA. Methylation modifies the function of the DNA, typically acting to suppress gene transcription.
5-methylcytosine-based DNA methylation occurs by the covalent addition of a methyl (CH 3) group at the 5-carbon of the cytosine ring resulting in 5-methylcytosine (5-mC). DNA methylation is a modifcation to DNA that occurs through the addition of a methyl group to DNA strand itself, often to the 5 carbon position of a cytosine ring. DNA methylation is the biological process by which a methyl group, which is an organic functional group with the formula CH 3, is added to DNA nucleotide. DNA, or deoxyribonucleic acid, is an important nucleic acid that stores the genetic information for any given organism. DNA methylation is a heritable epigenetic mark involving the covalent transfer of a methyl group to the C-5 position of the cytosine ring of DNA by DNA methyltransferases (DNMTs). In plants, cytosines are methylated in both symmetrical (CG or CHG) or asymmetrical (CHH, where H is A, T, or C) contexts. DNA methylation can stably alter the expression of genes in cells as cells divide and differentiate from embryonic stem cells into specific tissues. The resulting change is normally permanent and unidirectional, preventing a cell from reverting to a stem cell or converting into a different cell type. DNA methylation is a process by which methyl groups are added to DNA. Methylation modifies the function of the DNA, typically acting to suppress gene transcription. 10 most extreme places on Earth. DNA methylation is the biological process by which a methyl group, which is an organic functional group with the formula CH 3, is added to DNA nucleotide. DNA, or deoxyribonucleic acid, is an important nucleic acid that stores the genetic information for any given organism. There are many ways that gene expression is controlled in eukaryotes, but methylation of DNA (not to be confused with histone methylation) is a common epigenetic signaling tool that cells use to lock genes in the off position. Equally important and coupled with DNA methylation is DNA demethylation, the removal of a methyl group. The demethylation process is necessary for epigenetic reprogramming of genes and is also directly involved in many important disease mechanisms such as tumor progression.
http://www.whatisepigenetics.com/dna-methylation/ http://helicase.pbworks.com/w/page/17605615/DNA%20Methylation http://www.wisegeek.com/what-is-dna-methylation.htm http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3174260/ https://en.wikipedia.org/wiki/DNA_methylation https://en.wikipedia.org/wiki/DNA_methylation http://www.wisegeek.com/what-is-dna-methylation.htm http://www.nature.com/scitable/topicpage/The-Role-of-Methylation-in-Gene-Expression-1070 http://www.whatisepigenetics.com/dna-methylation/
what is dna methylation