Fig. 7. Effect of loss of Spry4 function on embryonic development. (A,B) Dorsal view of 10-somite stage embryos stained for pax2.1, myod and shh. Inhibition of Spry4 function by injection of spry4 morpholino (@S4) induces a lateral expansion of the somites (B). (C,D) embryos at late blastula stage on lateral view. Upon injection of @spry4 expression of BMP2b is strongly reduced in ventral blastomeres. (E, F) Lateral view of embryos at the 10-somite stage, labeled for krox20, engrailed 2 (eng2) and emx1. Injection of @spry4 causes a strong enlargement of emx1 expression in telencephalon. (G,H). Lateral cephalic view of 36 hour embryos. Embryos display facial outgrowings (arrowhead) following the injection of @Spry4, probably resulting from early enlargement of telencephalon.