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Fig. 3. Polar cells are required to specify stretched cells. (A,B) fng
mosaic follicles stained with Hoechst (DNA, white) and antibodies recognizing
-MYC (fng+ cells, green), ß-galactosidase
(MA33, stretched cells, red) and FasIII (polar cells, cyan). (A)
Stage 9 follicle with no fng+ anterior cells. No anterior
polar cells form and no stretched cells are specified. Arrowhead indicates
posterior polar cells. (B) Stage 10B follicle with only a few
fng+ cells at the anterior, including the polar cells
(inset). The polar and stretched cells are specified properly, even though
almost all stretched cells are fng-.