0896-62732231999MarNeuronEphrinB ligands recruit GRIP family PDZ adaptor proteins into raft membrane microdomains.511524511-24Transmembrane ephrinB proteins have important functions during embryonic patterning as ligands for Eph receptor tyrosine kinases and presumably as signal-transducing receptor-like molecules. Consistent with "reverse" signaling, ephrinB1 is localized in sphingo-lipid/cholesterol-enriched raft microdomains, platforms for the localized concentration and activation of signaling molecules. Glutamate receptor-interacting protein (GRIP) and a highly related protein, which we have termed GRIP2, are recruited into these rafts through association with the C-terminal PDZ target site of ephrinB1. Stimulation of ephrinB1 with soluble EphB2 receptor ectodomain causes the formation of large raft patches that also contain GRIP proteins. Moreover, a GRIP-associated serine/threonine kinase activity is recruited into ephrinB1-GRIP complexes. Our findings suggest that GRIP proteins provide a scaffold for the assembly of a multiprotein signaling complex downstream of ephrinB ligands.BrücknerKKDevelopmental Biology Programme, European Molecular Biology Laboratory, Heidelberg, Germany.Pablo LabradorJJScheiffelePPHerbAASeeburgP HPHKleinRRengGENBANKAF072509AJ133439Journal ArticleResearch Support, Non-U.S. Gov't