NATURE STRUCTURAL & MOLECULAR BIOLOGY | ARTICLE
Identification of methylated deoxyadenosines in vertebrates reveals diversity in DNA modifications
Magdalena J Koziol, Charles R Bradshaw, George E Allen, Ana S H Costa, Christian Frezza & John B Gurdon
Nature Structural & Molecular Biology (2015)
Received 22 July 2015 Accepted 18 November 2015 Published online 21 December 2015
Methylation of cytosine deoxynucleotides generates 5-methylcytosine (m5dC), a well-established epigenetic mark. However, in higher eukaryotes much less is known about modifications affecting other deoxynucleotides. Here, we report the detection of N6-methyldeoxyadenosine (m6dA) in vertebrate DNA, specifically in Xenopus laevis but also in other species including mouse and human. Our methylome analysis reveals that m6dA is widely distributed across the eukaryotic genome and is present in different cell types but is commonly depleted from gene exons. Thus, direct DNA modifications might be more widespread than previously thought.
Subject terms: DNA DNA methylation