The Role and Mechanism of TEAD4 in Preimplantation Embryonic Development in Mice and Cattle
Tead4 is a critical transcription factor expressed during preimplantation development and is essential for the expression of trophectoderm-specific genes in mice. However, the mechanism of Tead4's function in mouse preimplantation development and its conservation across mammals remains unclear. Here, we report that Tead4 is a crucial transcription factor necessary for blastocyst formation in mice. Disruption of TEAD4 through base editing results in developmental arrest at the morula stage. Additionally, RNA-seq analysis reveals dysregulation of 670 genes in Tead4 knockout embryos. As anticipated, Tead4 knockout leads to a decrease in trophectoderm genes CDX2 and GATA3. Intriguingly, we observed a reduction in KRT8, suggesting that Tead4 influences the integrity of the trophectoderm epithelium in mice. More importantly, we noted a decrease in nuclear YAP for Tead4-deficient embryos, indicating that Tead4 directly regulates Hippo signaling. In contrast, bovine embryos with TEAD4 depletion can still develop to blastocysts with normal expression of CDX2, GATA3, and SOX2, albeit with a decrease in total cell number and ICM cell number. In conclusion, we propose that Tead4 regulates mouse blastocyst formation via Krt8 and Yap, both of which are critical regulators of mouse preimplantation development. Overall design: PolyA RNA profiles of  bovine and mouse embryos