Tead4 and Tfap2c generate bipotency and a bistable switch in totipotent embryos to promote robust lineage diversification by Zhu, M, Meglicki, M, Lamba, A, Wang, P, Royer, C, Turner, K, Jauhar, MA, Jones, C, Child, T, Coward, K, Na, J, Zernicka-Goetz, M