Placental gene editing via trophectoderm-specific Tat-Cre/loxP recombination.

The ways in which placental defects affect embryonic development are largely overlooked because of the lack of a trophoblast-specific approach for conditional gene ablation. To tackle this, we have established a simple, fast and efficient method for trophectodermal Tat-Cre/loxP recombination. We used the natural permeability barrier in mouse blastocysts in combination with off-the-shelf Tat-Cre recombinase to achieve editing of conditional alleles in the trophoblast lineage. This direct approach enables gene function analysis during implantation and placentation in mice, thereby crucially helping to broaden our understanding of human reproduction and development.