Whole genome bisulfite sequencing (WGBS) of Tex15 wt, Tex15 ht, and Tex15 ko male germ cells at postnatal day 2.5. Whole genome bisulfite sequencing (WGBS) of Tex15 wt, Tex15 ht, and Tex15 ko male germ cells at postnatal day 2.5

DNA methylation is a major silencing mechanism of transposable elements (TEs). Here we report that TEX15, a testis-specific protein, is required for TE silencing. Through WGBS, we find that Tex15 mutant germ cells exhibit DNA hypomethylation in TEs. Our results identify TEX15 as a new essential epigenetic regulator that appears to function independently or downstream of the piRNA biogenesis machineries to silence TEs by DNA methylation in male germ cells. Overall design: We report hypomethylation in retrotransposons in Tex15-/- male germ cells at day 2.5 WGBS-seq of Tex15+/+, Tex15+/-, and Tex15-/- male germ cells at postnatal day 2.5 in biological duplicates (75PE-HiSeq4000); Germ cells were FACS-sorted (Oct4-GFP) from testes of pups from Tex15+/- x Tex15+/- matings.