Fig. 8. The so mutant phenotype in the ovary. (A) Nomarski optics images of a wild-type ovariole stained for ß-galactosidase activity to reveal the expression pattern of so⁵-lacZ in stalk cells (arrows) after stage 3. (B-D) Fluorescence images of two so mutant egg chambers (e1 and e2). (B) In the e1 egg chamber most follicle cells are mutant for so (lack GFP). In the e2 egg chamber, about half of the follicle cells are mutant for so and lack GFP (e2). (C) DAPI staining of the same two egg chambers. (D) Polar cells (arrows), revealed by anti FAS3 staining, develop normally. Scale bar: 50 µm.