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Fig. 6. Polar cells localize the oocyte and establish the AP axis. (A,B)
fng mosaic follicles stained with Hoechst (DNA, white) and antibodies
recognizing
-MYC (wild-type cells, green) and FasIII (polar cells, red).
(A) Stage 6 follicle with no posterior polar cells; the oocyte (asterisk) is
at the anterior, in contact with the anterior polar cells (arrow). (B) Stage 5
follicle with ectopic lateral polar cells and no posterior polar cells. The
oocyte (asterisk) is ectopically localized, in contact with the lateral polar
cells (arrow). (C,D) Germaria stained with phalloidin (F-actin, blue) and
antibodies recognizing Bic-D (oocyte, red). (C) Wild type. At stage 1, the
oocyte (arrow) is located at the posterior of the cyst (D) fng mosaic
marked with
-MYC (fng+ cells, green). In a stage 1
mutant follicle, the oocyte (arrow) is in the center of the cyst. (E,G,I)
Wild-type follicles and (F,H,J) fng mosaic follicles stained with
X-gal (blue/turquoise, pntS99812 in E,F; kin:lacZ
in G,H; nod:lacZ in I,J) and antibodies recognizing FasIII (polar
cells, black/brown). In F,H,J, the polar cells (arrow) are ectopically
localized to the side of the follicle, but (F) the follicle cells surrounding
them adopt a posterior identity, and (H,J) the AP axis of the oocyte
(asterisk) is correctly oriented with respect to the polar cells.