Evolution of dorsal-ventral patterning mechanisms in sibling Drosophila species

Case Western Reserve University, Cleveland OH

Investigators

Abstract

Previous studies revealed a high degree of conservation of the molecular mechanisms that establish embryonic tissues in diverse taxa. However, there are long-standing problems of great significance regarding pattern formation that remain largely unknown. Among those are the mechanisms of scaling and how novel body architectures are acquired, while some patterns are preserved during the course of evolution. This project will investigate the scaling properties during the formation of primary embryonic germ layers along the dorso-ventral axis in species that differ in egg size. To address these questions, the investigator will make cross-species comparisons among Drosophilids that diverged recently, but acquired sharp variation in egg size. The experiments will include quantitative measurements of morphogenetic gradients and gene expression patterns in different Drosophilids. In addition, two closely related Drosophila species that can hybridize, D. melanogaster and D. sechellia, will allow genetic experimentation to test species-specific contribution of maternal versus zygotic morphogenetic information to embryonic patterning. The results of this project are expected to produce critical quantitative data necessary to analyze the scaling properties of developmental systems and develop future computational models to explain how patterns are re-scaled with size. Broader impacts of this project include training at undergraduate and graduate levels, inclusion of minority groups to science, and improvement of curricula in the areas of developmental biology, evolution and modeling.