Fig. 4. Akap200 mutants produce binucleate nurse cells. (A) Wild-type stage ten egg chamber, stained with DAPI (blue) and rhodamine-conjugated phalloidin (red). Note the ring canal (arrowhead). (B) Similarly staged Akap200^k07118/Df(2L)N22-14 egg chamber, stained with DAPI and rhodamine phalloidin. Two binucleate nurse cells with ring canal remnants are indicated with arrowheads. (C-E) Expressing Pka-C throughout the germline with the GAL4/UAS system produces binucleate nurse cells. (C) Expression pattern of GAL4 line NGT40, visualized in NGT40/UAS-GFPnls ovaries. GAL4 expression was weak in this line, and was only detectable in germline cells in the germarium. (D) Expression pattern of GAL4 line nos-GAL4-VP16, visualized in nos-GAL4-VP16/UAS-GFPnls females. GAL4 expression was much stronger in this line, and highest in the germline cells in the germarium and after approximately stage seven. (E) Egg chambers from NGT40/UAS-PkaC* females, stained with DAPI to visualize nuclei (blue) and rhodamine phalloidin (red). Note the binucleate nurse cell with a ring canal remnant (arrowhead). Binucleate cells with identical morphologies were observed in nos-GAL4-VP16/UAS-Pka-C* ovaries. In C,D, the membrane and ring canal staining is due to bleed-through from the rhodamine-phalloidin channel.