Wednesday, November 4, 2009: 9:40 AM
Longhorn (Camino Real Hotel)
RhoGTPases play an important role in actin-dependant cell functions such as cell motility. The work here investigates whether RhoGTPases may function in the formation of dorsal appendages, the respiratory tubes for the Drosophila egg. In other tissues, Rho and Myosin II are required for tube formation and morphogenesis. Also, the regulation of transmission signaling between active GDP and inactive GTP states of RhoGAP and RhoGEF family proteins can be controlled by Decapentaplegic (DPP) signaling, which controls epithelial morphology. Since DPP and EGFR signaling control the patterning of the follicular epithelium, we hypothesize that RhoGAPs and RhoGEFs, which regulate GTPases, may mediate DPP and EGFR signaling in the follicular epithelium to control morphology of dorsal appendages. This process is thought to involve the following pathway: Rho, the Guanosine triphosphate (GTP)-bound active protein, activates Rho-kinase (ROK/Rock), which then phosphorylates the myosin light chain (MLC), regulating myosin II to act on actin, initiating cell motility. Using in-situ hybridization, we have shown that three of the 48 RhoGAP and RhoGEF genes are expressed in distinct patterns in the follicular epithelium.