Fig. 7. Persistent failure of midline neural convergent extension in Xdd1 injected embryos. (A) Control embryos stained for Xfd12 expression at stage 10.5. (B) Xdd1-injected embryos stained for Xfd12 at stage 10.5. (C) Control embryos stained for Xfd12 expression at stage 11.5. (D) Xdd1-injected embryos stained for Xfd12 at stage 11.5. (E) Expression of Xnetrin in control embryo at mid-neurulation. (F) Expression of Xnetrin in two Xdd1-injected embryos at mid-neurulation; green arrow indicates gap in Xnetrin expression domain. (G) Expression of Xnetrin in control embryo at late neurulation. (H) Expression of Xnetrin in two Xdd1-injected embryos at late neurulation; green arrow indicates gap in Xnetrin expression domain; red arrow indicates area at posterior floor of the open NT, which does not express Xnetrin. (I) Expression of SHH in control embryo at late neurulation (embryo has been cleared). (J) Expression of SHH in two Xdd1-injected embryos at late neurulation; green arrow indicates gap in SHH expression domain; red arrow indicates area in the floor of the open NT, which does not express SHH.