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.