Fig. 3. Innervation of the dorsal IPN requires Nrp1a. Dorsal views of habenular nuclei (A,B,G,H) and lateral views of the IPN (C,D,E,F,I) of 4-day-old larvae. (A-D) Mock-injected (A,C) or Nrp1a MO-injected (B,D) larvae were labeled with anti-Lov (red) and anti-Ron antibody (green). (E,F,I) Mock-injected (E), Nrp1a MO-injected (F) or parapineal-ablated (I) larvae were labeled at 4 days with DiI (red) in the left habenula. (G) All control-ablated larvae (n=27) had an intact parapineal (black arrowhead) as confirmed by otx5 expression (blue), and strong nrp1a expression (orange) in the left habenula. (H) In the majority of parapineal-ablated larvae, nrp1a expression (orange) was greatly reduced in the left habenula (71%, n=39). Scale bars: 50 µm.