Fig. 2. ascl1a is expressed in the adenohypophysis and the adjacent diencephalon. All panels show double (A-F) or single (G-L) in situ hybridization with probes indicated in the lower right-hand corners and ages of specimen in the upper right-hand corners. (B,D,F) Same embryos as in (A,C,E), after the red staining has been washed out. (A-F) Dorsal views, anterior towards the left; (G-L) lateral views, anterior towards the left, dorsal upwards. Arrows indicate adenohypophysis (G-L) or its anlage at the anterior neural ridge (A-F). ah, adenohypophysis; nh, neurohypophysis; pvh, posterior-ventral hypothalamus.