Catecholamine-induced desensitization of adenylate cyclase coupled. beta. -adrenergic receptors in turkey erythrocytes: evidence for a two-step mechanism

Journal Article · Tue Sep 08 00:00:00 EDT 1987 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00392a042· OSTI ID:5768593

Stadel, J M; Rebar, R; Crooke, S T

Preincubation of turkey erythrocytes with isoproterenol is associated with (1) 50-60% attenuation of agonist-stimulated adenylate cyclase activity, (2) altered mobility of the ..beta..-adrenergic receptor on sodium dodecyl sulfate-polyacrylamide gels, and (3) increased phosphorylation of the ..beta..-adrenergic receptor. Using a low-cross-linked polyacrylamide gel, the ..beta..-adrenergic receptor protein from isoproterenol-desensitized cells, labeled with /sup 32/P or with the photoaffinity label /sup 125/I-(p-azidobenzyl)carazolol, can be resolved into a doublet (M/sub r/ similarly ordered 37,000 and M/sub r/ similarly ordered 41,000) as compared to a single M/sub r/ similarly ordered 37,000 ..beta..-adrenergic receptor protein from control erythrocytes. The appearance of the doublet was dependent on the concentration of agonist used to desensitize the cells. Incubation of erythrocytes with dibutyryl-cAMP did not promote formation of the doublet but decreased agonist-stimulated adenylate cyclase activity 40-50%. Limited-digestion peptide maps of /sup 32/P-labeled ..beta..-adrenergic receptors using papain revealed a unique phosphopeptide in the larger molecular weight band (M/sub r/ similarly ordered 41,000) of the doublet from the agonist-desensitized preparation that was absent in the peptide maps of the smaller band (M/sub r/ similarly ordered 37,000), as well as control or dibutyryl-cAMP-desensitized receptor. These data provide evidence that maximal agonist-induced desensitization of adenylate cyclase coupled ..beta..-adrenergic receptors in turkey erythrocytes occurs by a two-step mechanism.

• Research Organization: Smith Kline and French Labs., Philadelphia, PA
• OSTI ID: 5768593
• Journal Information: Biochemistry; (United States), Vol. 26:18
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
CATECHOLAMINES
AUTORADIOGRAPHY
CYCLASES
BIOCHEMISTRY
AMP
ELECTROPHORESIS
ERYTHROCYTES
FOWL
IODINE 125
LABELLED COMPOUNDS
PHOSPHORUS 32
PHOSPHORYLATION
RECEPTORS
AMINES
ANIMALS
AROMATICS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BIRDS
BLOOD
BLOOD CELLS
BODY FLUIDS
CHEMICAL REACTIONS
CHEMISTRY
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
LIGHT NUCLEI
LYASES
MATERIALS
MEMBRANE PROTEINS
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHENOLS
PHOSPHORUS ISOTOPES
POLYPHENOLS
PROTEINS
RADIOISOTOPES
VERTEBRATES
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