FIG. 7.

Role of Fasciclin 3 (FAS3) in dorsolateral eggshell appendage (DA) morphogenesis. Top panels: Stage 10-12 egg chambers stained for FAS3 (green) or rhomboid-lacZ (magenta). Anterior is to the left. Lower panels: Magnified views of DA stalks on laid eggs. (A) Stage 10 dorsal view showing high FAS3 levels in the “T,” including the floor cells, and lower levels in main body follicle cells. Inset (a’) shows differential staining on floor-cell surfaces adjacent to roof cells. (B, b’) Lateral view of stage-10 egg chamber highlights differential FAS3 levels. (C) Dorsolateral view of a stage-12 egg chamber showing high FAS3 levels in floor cells and operculum cells. Note filopodia extending from basal surfaces of floor cells. (D) Wild-type DAs have a rounded stalk. (E) Fas3 mutant DAs are broad and flat along their entire length, not just at the paddle. The top panels are taken from Ward and Berg.⁵⁰