Fig. 8 Notch is required to specify polar cells. (A-D) N^55e11 clones marked with -Myc (green), and stained for nuclei (white) and Fas III (A,C), A101 (B) or E-Cadherin (D) (red). In all panels, arrows indicate polar cells and arrowheads point to Notch^- clones. (A) Stage 8 follicle. Notch^- cells express Fas III. (B) Stage 5 follicle. No A101 expression is detected in Notch^- cells within the follicular epithelium. (C) Stage 5 follicle. No Fas III expression is detected in the Notch^- cells within the follicular epithelium. The arrowhead points to the absence of Fas III-expressing polar cells. (D) Stage 3 follicle with only ten Notch⁺ cells at the anterior and three Notch⁺ cells at the posterior. The follicle appears normal and includes polar cells.