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5-Formylcytosine can be a stable DNA modification in mammals.

ABSTRACT: 5-Formylcytosine (5fC) is a rare base found in mammalian DNA and thought to be involved in active DNA demethylation. Here, we show that developmental dynamics of 5fC levels in mouse DNA differ from those of 5-hydroxymethylcytosine (5hmC), and using stable isotope labeling in vivo, we show that 5fC can be a stable DNA modification. These results suggest that 5fC has functional roles in DNA that go beyond being a demethylation intermediate.

SUBMITTER: Bachman M

PROVIDER: S-EPMC5486442 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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5-Formylcytosine can be a stable DNA modification in mammals.

Bachman Martin M Uribe-Lewis Santiago S Yang Xiaoping X Burgess Heather E HE Iurlaro Mario M Reik Wolf W Murrell Adele A Balasubramanian Shankar S

Nature chemical biology 20150622 8

5-Formylcytosine (5fC) is a rare base found in mammalian DNA and thought to be involved in active DNA demethylation. Here, we show that developmental dynamics of 5fC levels in mouse DNA differ from those of 5-hydroxymethylcytosine (5hmC), and using stable isotope labeling in vivo, we show that 5fC can be a stable DNA modification. These results suggest that 5fC has functional roles in DNA that go beyond being a demethylation intermediate. ...[more]

PMID: 26098680

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5-Hydroxymethylcytosine is a predominantly stable DNA modification.

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5-Formylcytosine does not change the global structure of DNA.

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