Fig. 6. Ventral spinal cord patterning defects in Disp mutants are rescued by N-Shh. Floorplate and ventral progenitors see in wild type (A,G) are not induced in Disp1^C829F/C829F mutants (B,H). Similarly, floorplate and pV3 progenitors (Nkx2.2⁺) cells are not induced in Disp1^C829F/2, Shh^+/- mutant (E,K). N-Shh signaling induces floorplate and ventral neural progenitors in the absence of Disp1 activity in Disp1^C829F/C829F; NShh^C/Shhⁿ; Sox2Cre mutant (D,J) and in Disp1^C829F/2, N-Shh^C/Shhⁿ, Sox2Cre embryos (F,L), similar to the pattern observed in N-Shh^C/Shhⁿ, Sox2Cre (C,I) embryos. Shh signaling is restored in the ventral neural tube as shown by Ptch1 expression (M-R). Although N-Shh is not detected by immunofluorescence in the floorplate of N-Shh^C/Shhⁿ, Sox2Cre embryos (C,D,F, compare with A), Shh is expressed at the ventral midline, indicating that floorplate induction has occurred (S-X) in the floorplate of N-Shh^C/Shhⁿ, Sox2Cre embryos independent of Disp1 activity.