Catecholamine-induced desensitization of turkey erythrocyte adenylate cyclase is associated with phosphorylation of the beta-adrenergic receptor.

Published

Journal Article

Preincubation of turkey erythrocytes with catecholamines desensitizes the beta-adrenergic receptor-adenylate cyclase complex in the plasma membranes of these cells. Photoaffinity labeling of the beta-adrenergic receptors with 125I-labeled p-azidobenzylcarazolol (125I-pABC) and subsequent analysis by NaDodSO4/polyacrylamide gel electrophoresis demonstrates an altered mobility of receptor peptides from desensitized cells compared to controls [Stadel, J.M., Nambi, P., Lavin, T.N., Heald, S.L., Caron, M.G. & Lefkowitz, R.J. (1982) J. Biol. Chem. 257, 9242-9245]. The time course of alteration in beta-adrenergic receptor mobility correlates with that for desensitization of isoproterenol-stimulated adenylate cyclase activity. The altered mobility of the receptor peptides from desensitized cells is also observed if the receptors are first purified and then photoaffinity labeled with 125I-pABC. The cyclic nucleotide analog 8-bromoadenosine 3',5'-cyclic monophosphate partially mimics catecholamines in promoting desensitization of the adenylate cyclase and modification of the receptor. Phosphorylation of the beta-adrenergic receptor in intact turkey erythrocytes was assessed by preincubating the cells with [32P]orthophosphate, desensitizing them with catecholamine, purifying the receptors, and then subjecting them to NaDodSO4/polyacrylamide gel electrophoresis. Desensitization is associated with a 2- to 3-fold increase in 32P incorporation into the receptor, which also demonstrates the characteristic alterations in mobility. These effects are blocked by the beta-adrenergic antagonist propranolol. Purified turkey erythrocyte beta-adrenergic receptors could be phosphorylated by incubation with [gamma-32P]ATP and the catalytic subunit of cAMP-dependent protein kinase. The mobility of the phosphorylated receptor peptides on NaDodSO4/polyacrylamide gel electrophoresis appears to correspond to that of the desensitized receptors. These data show that catecholamine-induced desensitization of adenylate cyclase in turkey erythrocytes correlates with a stable modification of the beta-adrenergic receptor and is associated with agonist-promoted phosphorylation of beta-receptor peptides.

Full Text

Duke Authors

Cited Authors

  • Stadel, JM; Nambi, P; Shorr, RG; Sawyer, DF; Caron, MG; Lefkowitz, RJ

Published Date

  • June 1, 1983

Published In

Volume / Issue

  • 80 / 11

Start / End Page

  • 3173 - 3177

PubMed ID

  • 6304694

Pubmed Central ID

  • 6304694

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.80.11.3173

Language

  • eng

Conference Location

  • United States