MeDIP-seq and RNA-seq analysis during porcine testis development reveals functional DMR at the promoter of LDHC.

Testis development requires tight regulation of gene expression programmed by epigenetic modifiers. However, their mechanism remains to be elucidated. Here, we investigated the genome-wide DNA methylation landscape in the Duroc and Meishan boar testes using methylated DNA immunoprecipitation sequencing (MeDIP-seq). We identified over 1100 promoter differential methylation genes (DMGs) before and after puberty, most of which are associated with testis development. Furthermore, we discovered that the expression of lactate dehydrogenase C (LDHC) gene during testis development is regulated by DNA methylation. The promoter of LDHC in pre-pubertal testes is substantially methylated, whereas considerably demethylated in post-pubertal testes. Artificial demethylation with the demethylating agent 5-Aza-CdR induced LDHC expression in immature Sertoli cells (SCs). Mechanistically, we confirmed the transcription factor SP1 was recruited to bind in hypomethylated differentially methylated regions (DMRs) in LDHC promoter, which upregulated the expression of LDHC. Functionally, we demonstrated that LDHC was activated in mature SCs (mSCs) and its overexpression significantly increases lactate secretion in SCs. In conclusion, our results highlight the function and regulation of dynamic DNA methylation in testis development.