title: GFRalpha-mediated localization of RET to lipid rafts is required for effective downstream signaling, differentiation, and neuronal survival.
abstract: The GDNF family ligands (GFLs: GDNF, neurturin, persephin, and artemin) signal through RET and a gly-cosyl-phosphatidylinositol (GPI)-anchored coreceptor (GFRalpha1-alpha4) that binds ligand with high affinity and provides specificity. The importance of the GPI anchor is not fully understood; however, GPI-linked proteins cluster into lipid rafts, structures that may represent highly specialized signaling organelles. Here, we report that GPI-anchored GFRalpha1 recruits RET to lipid rafts after GDNF stimulation and results in RET/Src association. Disruption of RET localization using either transmembrane-anchored or soluble GFRalpha1 results in RET phosphorylation, but GDNF-induced intracellular signaling events are markedly attenuated as are neuronal differentiation and survival responses. Therefore, proper membrane localization of RET via interaction with a raft-localized, GPI-linked coreceptor is of fundamental importance in GFL signaling.
authors.affiliation: Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: M G
authors.initials: MG
authors.lastname: Tansey
authors.forename: R H
authors.initials: RH
authors.lastname: Baloh
authors.forename: J
authors.initials: J
authors.lastname: Milbrandt
authors.forename: E M
authors.initials: EM
authors.lastname: Johnson
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002458:Cell Fractionation; D002462:Cell Membrane / Q000737:chemistry; D002470:Cell Survival / Q000502:physiology; D002531:Cerebellum / Q000166:cytology; D003902:Detergents; D029721:Drosophila Proteins; D005816:Genetic Complementation Test; D051100:Glial Cell Line-Derived Neurotrophic Factor; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D049452:Green Fluorescent Proteins; D007202:Indicators and Reagents; D008024:Ligands; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis*; D008164:Luminescent Proteins; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins / Q000494:pharmacology; D009447:Neuroblastoma; D009474:Neurons / Q000737:chemistry* / Q000166:cytology / Q000201:enzymology*; D018696:Neuroprotective Agents / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000032:analysis* / Q000378:metabolism; D051096:Proto-Oncogene Proteins c-ret; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis* / Q000378:metabolism; D020917:Receptor, trkA / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D012995:Solubility; D014407:Tumor Cells, Cultured; D019061:src-Family Kinases / Q000378:metabolism*
chemical_list: D003902:Detergents; D029721:Drosophila Proteins; C495041:Gdnf protein, rat; D051100:Glial Cell Line-Derived Neurotrophic Factor; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D007202:Indicators and Reagents; D008024:Ligands; D008055:Lipids; D008164:Luminescent Proteins; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases; D020917:Receptor, trkA; C416649:Ret protein, Drosophila; C495001:Ret protein, rat; D019061:src-Family Kinases