Fig. 1.

Balancing the stem-cell seesaw, a theory to explain how FGF signaling and WNT inhibition recapitulate pluripotency in cattle. Under standard primed culture condition, the potential bESC differentiate into mesendoderm cells in response to FGF and endogenous WNT. Bogliotti et al. (5) demonstrate the primed-state bESC can be stabilized by FGF2 supplementation and inhibition of WNT. The balance of lineage specification can result in a stabilized pluripotency state in cattle. Modified with permission from ref. 16.