title: Tyrosine kinase activity coupled to the high-affinity nerve growth factor-receptor complex.
abstract: Antibodies directed against nerve growth factor (NGF) immunoprecipitate a tyrosine kinase activity from NGF-treated PC12 rat pheochromocytoma cells. Based on several criteria, this activity has been correlated with the high-affinity and not the low-affinity NGF-receptor complex. The in vitro kinase activity and the tyrosine phosphorylation of the high-affinity complex can be blocked by an agent that inhibits NGF (and not epidermal growth factor)-induced tyrosine phosphorylation in PC12 cells, as well as NGF-induced neuronal differentiation of PC12 cells. These observations suggest that the high-affinity NGF-receptor complex is a substrate of tyrosine kinase activity. Phosphorylation reactions by the complex, performed in the absence of added substrate, label a single phosphopeptide of 130-135 kDa. This observation suggests that this phosphopeptide may represent the phosphorylation of the receptor kinase or the phosphorylation of a coimmunoprecipitating substrate, and possible signal-transducing molecule, of the high-affinity NGF-receptor complex.
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, CA 94305-5401.
authors.forename: S O
authors.initials: SO
authors.lastname: Meakin
authors.forename: E M
authors.initials: EM
authors.lastname: Shooter
mesh_terms: D000818:Animals; D046911:Macromolecular Substances; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000378:metabolism*; D010750:Phosphoproteins / Q000737:chemistry; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D010766:Phosphorylation; D019000:Phosphotyrosine; D011233:Precipitin Tests; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D051381:Rats; D011956:Receptors, Cell Surface / Q000502:physiology*; D017475:Receptors, Nerve Growth Factor; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D009414:Nerve Growth Factors; D010750:Phosphoproteins; D011956:Receptors, Cell Surface; D017475:Receptors, Nerve Growth Factor; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; D010751:Phosphopyruvate Hydratase