Meeting Abstract
The EGF pathway is a highly conserved and ubiquitously used cell signaling cascade in the development of many animals. In the highly studied Drosophila melanogaster, four ligands ( vein, gurken, spitz and keren) are used to activate the pathway while one ligand (argos) is used to repress activation of the EGF pathway. An arthropod centered phylogenetic analysis showed that the genes which encode the ligands Vein and Argos were present in the last common ancestor of all arthropods. However, this analysis showed the genes encoding Gurken evolved in the last common ancestor of the Diptera, the clade which includes flies. In continuation of this research, evidence was provided showing the orthologues of spitz and keren are the result of multiple independent gene duplication events. In an attempt to determine the ancestral role of the spitz/keren gene during insect development, we used RNAi targeting the orthologues of the genes in two separate lineages, Orthoptera and Hemiptera. These lineages are represented by the cricket Gryllus bimaculatus and the milkweed bug Oncopeltus fasciatus respectively.
