Fig. 4

Fig. 4 Progressive loss of FGF signaling results in loss of FGF-dependent gene expression and in expansion of Wnt-dependent gene expression. (A,B) FGF-dependent dkk1 expression is progressively lost between 27 and 35 hpf in the pLLp of mib1^ta52b zebrafish embryos (A), whereas the relative size of the lef1 expression domain progressively expands (B). Note that the lef1 domain becomes progressively smaller in the older wild-type pLLp. (C,D) Whereas cxcr4b expression (C) is not significantly changed in the mib1^ta52b pLLp (n=7 at 31 hpf and n=5 at 35 hpf), cxcr7b expression (D) is reduced in mib1^ta52b by 31 hpf (n=9 at 31 hpf and n=6 at 35 hpf).