Resf1 is required for normal placental development and configuration of trophoblast cell-specific heterochromatin [ChIP-seq]

However, it remains unknown whether Resf1 functions in retroelement silencing in vivo, and has a role in development. To address this question, we established Resf1-deficient mice.

The Resf1-deficient mice show developmental delay, partial embryonic lethality, and placental abnormalities. Remarkably, retroelements are also upregulated in the Resf1-deficient placenta, and this upregulation of retroelements correlates with elevated expression of nearby genes. Additionally, to determine whether Resf1 functions within the trophoblast lineage—given the heterogeneous cellular composition of the placenta—we established Resf1-deficient trophoblast stem cell (TSC) lines.