title: Identification of a nerve growth factor receptor protein in sympathetic ganglia membranes by affinity labeling.
abstract: Membranes from adult rabbit superior cervical ganglia, cross-linked to membrane-bound 125I-labeled nerve growth factor (NGF) by the photoreactive agent hydroxysuccinimidyl-p-azidobenzoate, were found to contain two labeled components with apparent Mr = 143,000 and Mr = 112,000. At high concentrations of the cross-linker, minor amounts of a Mr = 300,000 affinity labeled product were also observed. The affinity labeled species exhibit the characteristics expected of membrane receptors for NGF. The inhibition of specific 125I-NGF binding to membranes by increasing concentrations of unlabeled NGF parallels the inhibiton of the affinity labeling of these components. Insulin, insulin-like growth factor I, multiplication stimulating activity, and epidermal growth factor do not inhibit the affinity labeling reaction. Membrane preparations of various non-neuronal tissues do not show any detectable specific cross-linking to 125I-NGF. The affinity labeled species of superior cervical ganglia are proteins and contain intrapeptide disulfide bridges compacting their molecular structure. Peptide mapping experiments indicate a close structural relationship between the Mr = 143,000- and the Mr = 112,000-labeled proteins, suggesting a transformation of the former into the latter by limited proteolysis. The results suggest that the Mr = 143,000 affinity labeled protein represents a native NGF receptor component.
mesh_terms: D000345:Affinity Labels; D000818:Animals; D001386:Azides; D002462:Cell Membrane / Q000378:metabolism; D004229:Dithiothreitol / Q000494:pharmacology; D005728:Ganglia, Sympathetic / Q000378:metabolism*; D007700:Kinetics; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000378:metabolism*; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000302:isolation & purification / Q000378:metabolism*; D017475:Receptors, Nerve Growth Factor
chemical_list: D000345:Affinity Labels; D001386:Azides; D009414:Nerve Growth Factors; D011956:Receptors, Cell Surface; D017475:Receptors, Nerve Growth Factor; C029534:hydroxysuccinimidyl-4-azidobenzoate; D004229:Dithiothreitol