TitleThe glypican Dally is a target and mediator of BMP signaling in eggshell patterning
NameLemon, David James (author), Yakoby, Nir (chair), Martin, Joseph V. (internal member), Shain, Daniel H. (internal member), Rutgers University, Camden Graduate School,
Bone morphogenetic proteins,
DescriptionHeparan sulfate proteoglycans (HSPGs) participate in the regulation of numerous cell signaling pathways in tissues throughout animal development. In Drosophila melanogaster, the HSPG Division-abnormally-delayed (Dally) acts as a co-receptor in several signaling pathways, including bone morphogenetic protein (BMP) signaling, during imaginal wing disc development. Previously, it has been shown that dally is patterned in the follicle cells (FCs), a mono-layer of epithelial cells which surrounds the oocyte. These cells derive the formation of the eggshell. We found this pattern to be evolutionary conserved across Drosophila species. Also, dally’s pattern spatially overlaps the BMP signaling domain, which was monitored by phosphorylated-Mothers-against-Dpp (P-MAD). Using genetic perturbations, we determine that in the FCs, dally is a downstream target of BMP signaling. Furthermore, in clones of cells null for dally, P-MAD is lost cell autonomously. When dally was perturbed uniformly throughout the FCs the BMP signaling gradient was expanded or restricted in gain-of-function or loss-of-function, respectively. Consequently, the FCs patterning shifted along the anterior-posterior axis. Perturbing dally in the anterior domain of the FCs resulted in changes of eggshell morphology. Specifically, the depletion of dally results in an overall increase in operculum length. Based upon our results, and consistent with Dally’s role in wing imaginal discs, we propose a model by which Dally contributes to eggshell patterning along the anterior-posterior axis by regulating BMP signaling.
NoteIncludes bibliographical references
Noteby David James Lemon
CollectionCamden Graduate School Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.