Fig. 6.

TEAD4 mediated specification of TE and ICM lineages in a preimplantation mammalian embryo. The model illustrates that nuclear localization of TEAD4 in the outer TE lineage induces TE-specific genes like Gata3. TEAD4 nuclear localization positively autoregulates its own transcription and increases TEAD4 protein levels in the TE lineage. The high TEAD4 concentration facilitates its nuclear localization. The dotted line denotes other putative mechanisms, not yet supported by experimental evidence, which could regulate TEAD4 nuclear localization in polar outer cells. The model also predicts that low TEAD4, as well as the absence of other putative mechanisms, impairs TEAD4 nuclear localization in the ICM lineage, thereby limiting TEAD4 transcription and abrogating expression of other TE-specific genes, such as Gata3.