Fig. 5. Sxl expression in PKA, cos2 and Su(fu) mutant ovaries. (A-F) Germline clones are marked by the absence of ß-galactosidase (see Materials and Methods). (A-C) Germarium with cos2 clones stained for ß-galactosidase (A) and Sxl (B). (C) Merged image of (A,B). One of the early germ cells is positive for ß-galactosidase (cos2⁺), while the other germ cells are negative for ß-galactosidase (cos2^–). Expression of Sxl is normal in the cos2⁺ cell and very reduced in the cos2^– cells. All germarial clones counted appeared similar. (D-F) Germline clone of PKA null allele stained for ß-galactosidase (D) and Sxl (E). (F) Merged image of D,E. Two of the early germ cells are PKA–, and the accumulation of Sxl in the nucleus is stronger (arrow in F). (G) Su(fu)LP ovary stained for Sxl. Two chambers appear necrotic with degenerating follicle and germ cells. (H) Ovariole from doubly homozygous Sxlf4 and Su(fu)LP female stained for Sxl. Germ cells appear to be detaching from the follicle cell layer and degenerating.