Screening for regulatory sequences that pattern the Drosophila eggshell. Nicole Pope, Maira Farhat, Robert A. Marmion, Nir Yakoby. Biology, Rutgers University- Camden, Camden, NJ.

   Organogenesis relies on extensive tissue patterning by regulating the expression of genes in a spatiotemporal manner. During oogenesis, the follicle cells, a monolayer of epithelial cells surrounding the developing oocyte, are patterned to drive the formation of the Drosophila eggshell; an organ that shelters the developing embryo. While follicle cells patterning has been vastly documented, the regulatory domains that govern tissue patterning are mostly unknown. To find regulatory domains, we cross-listed the 81 genes known to be expressed during oogenesis with the large collection of the Rubins Lab GMR lines, and we found 19 common genes. These genes are represented by 230 GMR lines. Of great advantage, all GMR lines are driving the expression of a GAL4 thus providing an opportunity to screen these lines by crossing them to a UAS-GFP. Approximately 25% of the tested GMR lines express GFP during oogenesis, and 25% of those lines recapitulate the partial or full endogenous patterns of their corresponding genes. We found that regulatory information is enriched in certain positions of the genes locus. We also demonstrated the use of the GMR lines to disrupt eggshell morphologies. Our comprehensive screen identified multiple regulatory DNA fragments that governs eggshell patterning.