MCB9728324 Segall, Jeffrey This project is to understand the role of mitogen-activated protein kinases (MAP kinases) in chemotaxis and signaling responses of the amoeboid cells of the slime mold, Dictyostelium discoideum. This organism will be used as a biochemically and genetically accessible model system to delineate the molecular events by which MAP kinases activate adenylyl cyclase and give rise to changes in cell motility. The project will focus on the role of one kinase, designated DdERK2, which the principal investigator has already partially characterized. The project will now identify and characterize potential target proteins that DdERK2 phosphorylates. Approaches will include both an in vitro biochemical kinase assay and a yeast two-hybrid genetic assay. The functions of the target proteins identified by either approach will be tested by analysis of the phenotypes that result when the genes encoding the proteins are disrupted. Identification and detailed analysis of the proteins should provide an understanding of the sequential events in this signaling pathway, both in Dictyostelium and presumably other organisms.
