Characterization of adhesion and secretin GPCRs in the salivary glands and germ cells during Drosophila embryogenesis
Authors: Sean Riccard; Caitlin Hanlon
Affiliation: Quinnipiac University
Keywords: p. cell migration; p. cell migration
Embryogenesis requires coordinated cell migration directed by molecular guidance cues for proper tissue development. G-protein coupled receptors (GPCRs) are widely conserved transmembrane receptors that relay extracellular signals to the intracellular environment. Despite their prominence, GPCRs are understudied during Drosophila embryonic development. The adhesion and secretin GPCR subfamilies, characterized by their long N-terminal domains, are an interesting topic for further study because of their role in other developmental processes including cell adhesion and endocrine signaling. Adhesion GPCRs are highly expressed in mouse embryonic kidney structures, promote angiogenesis in cell culture, and are implicated in human skeletal development and disease. Secretin GPCRs are also implicated in human skeletal development as well as retinal angiogenesis in mice. Here, we used RNAi to tissue-specifically knockdown the adhesion and secretin GPCRs to determine their role in the embryonic salivary glands (SG) and germ cells (GC). We found that adhesion GPCRs influence Drosophila SG structure in the late embryo. Knockdown of CG11318 or CG15556 has resulted in irregular SG placement (p<0.05). Furthermore, Crumbs-stained SGs in embryos with a knockdown for CG15556 have shown that the apical domain of these SGs are uneven, not smooth and straight like the wild type SG. Interestingly, knocking down either of these gene types in the GCs has had no effect on GC migration. These findings suggest a role for adhesion GPCRs in proper embryonic SG migration. Our next steps are to observe SG migration in embryos with deficiency and insertion lines that cover CG11318, as well as characterize embryonic expression of CG11318 by in situ hybridization.