Fig. 5. mShhN is significantly more potent at inducing Nkx2.1 expression in rat head fold stage (0-4 somites) neural explants than uShhN. The blue region of the schematic shows the region of the headfold used in the explant assay. uShhN: A, 3070 nM; B, 384 nM; D, 48 nM; F, 24 nM; H, 12 nM. mShhN: C, 48 nM; E, 24 nM; G, 12 nM (n=4). Note that none of the controls treated with buffer alone contained Nkx2.1-positive cells (n=6).