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bioRxiv · 10.1101/177535

Transient Reduction of DNA Methylation at the Onset of Meiosis in Male Mice

Gaysinskaya, V.·Miller, B. F.·van der Heijden, G. W.·Hansen, K. D.·Bortvin, A.
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Abstract

The quality of germ cells depends on successful chromatin organization in meiotic prophase I (MPI). To better understand the epigenetic context of MPI we studied the dynamics of DNA methylation in wild-type male mice. We discovered an extended period of genome-wide transient reduction of DNA methylation (TRDM) during early MPI. Our data show that TRDM arises by passive demethylation in the premeiotic S phase highlighting the abundance of hemimethylated DNA in MPI. Importantly, TRDM unmasks a deficit in retrotransposon LINE-1 DNA methylation contributing to its expression in early MPI. We propose that TRDM facilitates meiosis and gamete quality control.

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Gaysinskaya, V., Miller, B. F., van der Heijden, G. W., Hansen, K. D., Bortvin, A.. 2017-08-17. Transient Reduction of DNA Methylation at the Onset of Meiosis in Male Mice. https://doi.org/10.1101/177535

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