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bioRxiv · 10.1101/2020.05.13.093203

Pervasive non-CpG methylation at zebrafish mosaic satellite repeats

Ross, S. E.·Angeloni, A.·de Mendoza, A.·Bogdanovic, O.
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Abstract

In vertebrates, DNA methylation predominantly occurs at CG dinucleotides even though widespread non-CG methylation (mCH) has been reported in mammalian embryonic and neural cells. Unlike in mammals, where mCH is found enriched at CAC/G trinucleotides and is tissue-restricted, we find that zebrafish embryos as well as adult somatic and germline tissues display robust methylation enrichment at TGCT positions associated with mosaic satellite repeats. These repeats reside in H3K9me3-marked heterochromatin and display mCH reprogramming coincident with zygotic genome activation. Altogether, this work provides insight into a novel form of vertebrate mCH and highlights the substrate diversity of vertebrate DNA methyltransferases.

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Ross, S. E., Angeloni, A., de Mendoza, A., Bogdanovic, O.. 2020-05-14. Pervasive non-CpG methylation at zebrafish mosaic satellite repeats. https://doi.org/10.1101/2020.05.13.093203

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