Disruption of Cell Adhesion inXenopusEmbryos by Pagliaccio, an Eph-Class Receptor Tyrosine Kinase

AbstractPagliaccio (Pag) is a receptor tyrosine kinase of the Eph family that is expressed inXenopusembryos in a diverse set of localized tissues. Pag is theXenopushomolog of Hek-8 (human), Sek-1 (mouse), cek8 (chicken), and RTK-1 (zebrafish). We have investigated the function of this protein by injecting RNA encoding an epidermal growth factor receptor–Pag chimera into earlyXenopusembryos. Activation of the chimeric receptor results in a kinase-dependent loss of cell–cell adhesion. This dissociation can be reversed by co-injection of RNA encoding C-cadherin, suggesting that one or more cadherins could be the functional targets for Pag activity