Abstract
Antibodies recognizing the Drosophila EGF receptor homolog (DER) were used to define the biochemical properties of the protein. We show that DER is a glycosylated protein, with different processing patterns in Drosophila and mammalian cells, and confirm its localization in the plasma membrane with the predicted orientation. The receptor produced in transfected cells displays only a basal activity of in vivo tyrosine kinase autophosphorylation, providing a sensitive assay for ligands which may trigger DER. EGF and TGF alpha, which trigger the mammalian EGF receptor, did not increase the kinase activity of DER.
