Fig. 5. Cad99C protein localizes to microvilli of follicle cells. (A-C) Follicle cells of a stage-10 wild-type egg chamber stained for (A) DE-cadherin and (C) Cad99C. (B) Merge of (A) and (C). DE-cadherin is shown in green and Cad99C in red. Apical is to the top. (D-F) Follicle cells of a stage-10 egg chamber expressing the membrane marker CD8-GFP (CY2, UAS-CD8-GFP) stained for (D) GFP and (F) Cad99C. (E) Merge of (D) and (F). Cad99C colocalizes with CD8-GFP to apical protrusions. Apical is to the top. (G,H) Electron micrographs of anti-Cad99C immunogold-labeled sections of stage-10 egg chambers of (G) heterozygous Cad99C^57A/+ or (H) homozygous mutant Cad99C^57A/57A flies. Insets show higher magnification views. 10 nm immunogold particles are detected on microvilli of heterozygous Cad99C^57A/+ follicle cells, but not homozygous mutant Cad99C^57A/57A follicle cells. Note that, in homozygous mutant Cad99C^57A/57A flies, microvilli (arrowheads) are observed more frequently between the vitelline bodies and the planar follicle cell surface compared with control flies. Oo, oocyte; Fc, follicle cells; Yg, Yolk granule; Vb, Vitelline body. Bars, 5 µm (A-F); 500 nm (G,H).