In situ hybridization analysis of Dlx3 at E12.5 (A) and Dlx1 (B), Rax (C) and Zhx1 (D) at E14.5 in the developing pituitary indicates robust expression. (A) At E12.5 Dlx3 is expressed strongly in the intermediate lobe (IL), shown by the white arrow, as well as in the posterior pituitary (PP) and throughout the expanding Rathke's pouch (RP), though predominantly in the dorsal aspect. The dorsal aspect is indicated by the black diagonal line. (B) At E14.5 Dlx1 is expressed throughout Rathke's pouch and the intermediate lobe. Expression appears concentrated in the ventral aspect of the pouch, as shown by the white arrow. Dlx1 expression is also present in the ventral diencephalon (VD). Rax (C) and Zhx1 (D) are expressed throughout the developing Rathke's pouch (RP). Sense controls corresponding to each gene are shown in the top left hand corner of each panel.