Fig. 7. Overexpression of Cad99C leads to large bundles of microvilli and vitelline membrane defects. (A,B) Follicle cells of stage-10 egg chambers expressing (A) CD8-GFP (CY2, UAS-CD8-GFP) or (B) CD8-GFP and Cad99C-HA (CY2, UAS-CD8-GFP, UAS-Cad99C-HA) stained for GFP. The CD8-GFP-labeled protrusions in follicle cells expressing Cad99C-HA form roof-like structures (asterisk). Apical is to the top. (C,D) Electron micrographs of anti-Cad99C immunogold-labeled sections of stage-10 (C) control egg chambers and (D) egg chambers expressing Cad99C-GFP (Act5C>GAL4, UAS-Cad99C-GFP) in clones of follicle cells. Overexpression of Cad99C-GFP results in large Cad99C-labeled bundles of follicle cell microvilli located in between vitelline bodies (Vb). Cad99C-labeled microvilli that are parallel and close to the oocyte surface are marked by an asterisk. (E,F) Electron micrographs of anti-sV17 10 nm immunogold-labeled sections of stage-12 (E) control egg chambers and (F) egg chambers expressing Cad99C-GFP (Act5C>GAL4, UAS-Cad99C-GFP) in clones of follicle cells. Long microvilli persist in follicle cells expressing Cad99C-GFP and the vitelline membrane (Vm) is disrupted (asterisk). Oo, oocyte; Fc, follicle cells. Bars, 5 µm (A,B); 500 nm (C-F).