ALT Figure 1: Assignment of transcriptomes to cell identities. (A) Experimental design for isolating single dorsal NT cells. (B,C) NTs electroporated at E2.5 and microdissected at E4, showing similar Msx1-Citrine labeling between control and RARα403 treatments. (D) UMAP of control and treated samples, colored by cluster with cell count indicated

ALT Alexandre Dumoulin (left) and Esther Stoeckli (right)

ALT Figure 10: The primary cilium is required for the regulation of Hhip transcription by Shh and, therefore, the switch in axon responsiveness at the floorplate. (A) Shh produced by the floorplate is retrogradely transported to the soma of commissural neurons, when their growth cones contact the intermediate target. Glypican 1 interacts with Shh at the growth cone and, by a yet unknown mechanism, Shh is transported retrogradely to the soma. A functional primary cilium and Smo localization to the cilium are required for commissural axon guidance. (B) Once commissural axons exit the floorplate, Hhip mediates the repulsive response to the caudalhigh-rostrallow Shh gradient and the rostral turn. Black rods represent unknown co-receptors. FP, floorplate; GPC1, glypican 1; r, rostral; c, caudal.