Dynamic remodeling of cell vertices in the Drosophila follicle epithelium
Vitellogenesis, the process of yolk formation in the oocyte, is a key process in the development of the oocyte and the posterior formation of a mature egg in all oviparous animals. The first step of yolk formation is the deposition of Yolk Protein (YP) (aka Vitellogenin) into the oocyte by clathrin-mediated endocytosis. In Drosophila the major part of the YP is synthetized in the fat body (the analog of the liver in insects) and has to be afterwards transported through the hemolymph to the egg chamber and cross the FE to reach the oocyte surface. For this purpose, follicular cells (FCs) shrink, creating transient intercellular channels at three-cell vertices that allow the paracellular transport of the YP. This condition, termed patency, even though described in the 70s, has not been further investigated and the cellular events underlying remain unknown.
In my project, I aim to shed light on the mechanisms triggering patency, focusing on the specific removal of adhesion proteins from three cell vertices, by the use of genetic and microscopy tools.