BMP4 initiates and patterns ventral-caudal structures in zebrafish and human pluripotent stem cell aggregates. - Xing YY; Huang Y; Cheng T; Tian YM; Dong Y; Jin ZX; Pu HR; Luo T; Liu X; Shen HN; Mo J; Ma J; et al. (The EMBO journal, 2026)