D3537: Development of functional genomics tools in cactophilic Drosophila

   The central aim of this project is to enhance the power of investigators to assess the relationship between genotypes and phenotypes in an ecological and comparative context by creating a customizable transgenic system. Here we describe the building of a transgenic toolkit the ecological model system of cactophilic Drosophila. 

   The cactophilic Drosophila system offers a unique opportunity to integrate genomics, functional genomics, transcriptomics and phenomics in an ecological and comparative context. Cactophilic Drosophila are endemic to the Americas and oviposit, develop, and feed as adults in the necrotic tissues of a variety of cactus species. The transgenic toolkit we are building uses the three most widely used cactophiles, D. mojavensis and D. arizonae from North America and D. buzzatii from South America. We recently generated de novo chromosome level genome assemblies and annotations for each of the four D. mojavensis cactus host populations, for two ecologically divergent D. arizonae populations and collaborated on a new comprehensive annotation of D. buzzatii. To build the toolkit we will: 1) generate lines with attP integration sites in several chromosomes using CRISPR; 2) use these lines to incorporate phiC31 integrase in the X chromosome of all three species; 3) perform detailed tissue, developmental and environment-dependent transcriptional analysis to identify driver loci; 4) generate tissue specific GAL4 driver lines and a UAS-GFP reporter; 5) generate a UAS-RNAi plasmid construct; and 6) disseminate the toolkit using the National Drosophila Species Stock Center, a dedicated online repository for information (Cactusflybase,  https://cactusflybase.arizona.edu/) and in-person workshops.