NUMB and NUMBLIKE are preferentially expressed early in pituitary development. Sagittal sections at e9.5 (A and D), e11.5 (B and E), and e12.5 (C and F) immunostained with NUMB (A–C) and NUMBLIKE (D–F), counterstained with DAPI. Both NUMB and NUMBLIKE are enriched in RP at e9.5. Arrow, ventricular zone. Pictures taken at ×200. Scale bar, 50 μm. RP, Rathke’s pouch; AL, anterior lobe; PL, posterior lobe.