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Title: Methylation of cytosine Post by: robinmjelle on Apr 12, 2015 Hi,
Why do most Cytosine methylations happen at CpG sites? Is it common that CpC, CpT or CpA are methylated? Best Title: Re: Methylation of cytosine Post by: bio_man on Apr 12, 2015 http://www.sciencedirect.com/science/article/pii/S0378111904000836
This paper should provide a decent answer to your question, except that it's looked. Do you have an account with ScienceDirect? Title: Re: Methylation of cytosine Post by: robinmjelle on Apr 13, 2015 The paper does not answer the questions, unfortunately.
Title: Re: Methylation of cytosine Post by: bio_man on Apr 13, 2015 The paper does not answer the questions, unfortunately. You downloaded it? Please share it if possible. Also, try these links, Robin: 1) https://books.google.ca/books?id=yMFN5dvgNscC&pg=PA620&lpg=PA620&dq=%22Cytosine+methylation+occurs+at%22+CpG&source=bl&ots=zI6rizY7-o&sig=ReJBapaZ-h1nJLX9g8sm2U4ookk&hl=en&sa=X&ei=g3IsVam-B5etyATsq4GABQ&ved=0CEMQ6AEwBg#v=onepage&q&f=false 2) https://books.google.ca/books?id=9hqpCR2yihkC&pg=PA231&lpg=PA231&dq=%22Cytosine+methylation+occurs+at%22+CpG&source=bl&ots=u2DXSNXaz5&sig=mQHPg0krcyQb7GCVo8JwOij7pJ4&hl=en&sa=X&ei=g3IsVam-B5etyATsq4GABQ&ved=0CD8Q6AEwBA#v=onepage&q&f=false 3) http://advances.nutrition.org/content/3/1/21.full Quote Methylation of cytosine is common throughout the human genome. This covalent modification most commonly occurs at cytosines within a 5′-CpG-3′ dinucleotide when a methyl group from S-adenosylmethionine (SAM)6 is enzymatically transferred to the 5 position of cytosine to generate 5-methylcytosine (5-MC) in genomic DNA. DNA methylation patterns are a product of the frequency of cytosine DNA methylation at specific sites along a strand of DNA. Recent genome-wide high-resolution DNA methylation analysis of a primary human fibroblast cell line demonstrated that 4.25% of total cytosines in genomic DNA are methylated, 67.7% of CpGs are methylated, and 99.98% of DNA methylation occurs in CpG dinucleotides (10). Similar analysis of a human embryonic stem cell line showed that 5.83% of cytosines are methylated, 82.7% of CpG dinucleotides are methylated, and 25% of all cytosine methylation occurs at non-CpG sites (10); an earlier study also reported high levels of non-CpG methylation in mouse embryonic stem cells in contrast to methylation patterns in mouse somatic cells (17). Although the importance of CpG methylation is established, the role of non-CpG methylation is a new active area of research. |