Figure 7.

Model of follicular patency regulation in Drosophila melanogaster

DAPI stained egg chambers as arranged in an ovariole, depicting germarium to St 13. Patency is observed in the oocyte-associated follicular epithelium as gaps between the cells from the basal to the apical domain, illustrated in the cross-sectional and top-down views. The strict temporal range of patency (St10a–10b) is regulated by Ttk69, and the mechanistic details are yet to be discovered. At stage 10b, the dorsalizing signals EGFR and Dpp create a spatial pattern of patency, illustrated as “intact TCs” at the dorsal anterior and “patent TCs” in the rest of the FE.