Fig. 8. PDGFR signaling is necessary during induction for opV trigeminal ganglion neurogenesis. (A) A st. 14 control embryo shows Pax3 (green) cells condensing into ophthalmic lobe of the trigeminal ganglion. (B) Hu/NF (red) staining of same section as A shows many of the Pax3+ cells are neurons. (C) Merge of A,B plus DAPI (blue). (D) At st.14, many fewer Pax3+ have condensed in 2.5 µm PIII embryos (injected at st. 8). (E) Similarly, fewer Hu/NF+ neurons were generated. (F) Merge of D,E plus DAPI. Arrows indicate double-labeled Pax3/Hu/NF cells.