Fig. S5
Antagonists of the FGF pathway can anteriorize ich embryos with impaired BMP signaling. Single in situ hybridization with cyp26 (A,D,G,J,M,P,S) or hoxb1b (B,E,H,K,N,Q,T) probes or double in situ hybridization with both probes (C,F,I,L,O,R,U) is shown for wild-type embryos (A-C), untreated ich embryos (D-F), ich embryos treated with bmp2bMO (G-I), injected with XFD or mkp3 mRNAs alone (J-L and P-R), or in combination with bmp2bMO (M-O and S-U). The injection of mRNAs encoding a dominant negative FGF receptor, XFD, or a negative regulator of the MAPK pathway, mkp3, into bmp2bMO-injected embryos results in the posterior expansion of the anterior neurectodermal marker, cyp26 (M,O, and S,U, and a reduction of the posterior neurectodermal domain, marked by hoxb1b (N,O and T,U). Gastrulation movements seem to be impaired in such coinjected embryos. These antagonists of FGF signaling have no effect on untreated ich embryos (J-L and P-R). Wild-type embryos (A-C) are shown in a dorsal view, ich embryos (D-U) in lateral view. All embryos are at ~10 hpf. |