Fig. 7. Phox2a is sufficient to induce noradrenergic neurones in r1. (A) At E8 DBH expression in wild-type embryos is not detected dorsal to the fourth ventricle (B, arrow). After injection of Phox2a-expressing RCAS vectors at stage 9, the dorsolateral alar plate, dorsal to the ventricle, is infected as visualised by the RT expression pattern (arrow). (B,C) In this infected E8 embryo, ectopic DBH (C) and TH-positive (D) neurones are observed dorsal to the fourth ventricle (arrows). The ventricle is indicated by a broken line.
