Investigation of Evi-Mediated Wnt/Wg secretion in Drosophila

Abstract

The Wnt/Wingless (Wg) signaling pathway is essential for many developmental processes in various organisms ranging from Drosophila to humans. Wnts are secreted glycoproteins that act on cells far away from the source of production. One good example of such function of Wnts is the patterning of Drosophila wing imaginal discs. The Boutros lab has identified a novel multipass transmembrane protein Evenness interrupted (Evi), which is required for the secretion of Wnt/Wg proteins across species. However, the mechanism by which Evi helps in secretion of Wnts remain poorly understood. Besides this, other protein(s) which help in Evi mediated Wnt/Wg secretion remain unidentified. We aim to analyze the mechanism of Evi-mediated Wg/Wnt secretion using in vivo RNAi screening method in Drosophila. Recently, a list of proteins (around 35) interacting with Evi is provided by the Drosophila Protein interaction Mapping project (DPiM). We knockdown genes from this list using the UAS-GAL4 expression system and analyze the effect on Wg secretion in Drosophila wing imaginal discs. This method let us to identify Rpt1 (CG1341), Pvr (CG8222) and an unknown protein (CG6724) as good candidates for further studies.