The Gag product of ZAM is restricted to the follicle cells when communication between the follicle cell and the oocyte is blocked. Double staining with Gag anti-body of ZAM (red) and YL1 antibodies (green) of stage 10 ovarian chambers. A) In ovaries of a U-line, the Gag protein of ZAM is detected in follicle cells (red staining), and colocalized with the yolk protein receptor (green) at the oocyte border (yellow). B) In [Xu/Xu; fs(2)A17/fs(2)A17] ovaries, the Gag product is restricted to the follicle cells. oo, oocyte; fc, follicle cells.