Maternal Vitamin C regulates DNA demethylation and devlopment of the mouse embryonic germline [Cut&Run]

Maternal Vitamin C is required in vivo for proper DNA demethylation and development of fetal germ cells in a mouse model of Vitamin C deficiency. Withdrawal of Vitamin C from the maternal diet does not affect overall embryonic development but leads to defects in the fetal germline, which persist well after Vitamin C re-supply during late gestation. The transcriptome of germ cells from Vitamin C-deficient embryos is remarkably similar to that of embryos carrying a mutation in Tet1, which is responsible for DNA demethylation and activation of regulators of meiosis. In agreement with these results, Vitamin C deficiency leads to an aberrant DNA methylation profile that includes incomplete demethylation of key regulators of meiosis and transposable elements. These findings reveal that deficiency in Vitamin C during gestation recapitulates a mutation in Tet1 and disrupts germline reprogramming and development. Our work further indicate that the embryonic germline is sensitive to perturbations of the maternal diet, providing a potential intergenerational mechanism for adjusting fecundity to environmental quality. Examination of H3K9me2 genome-wide enrichment in gonadal PGCs or soma from E13.5 female Gulo -/- embryos developed with and without Vitamin C supplementation. 3-5 biological replicates per condition.