Agonist photoaffinity label for the. beta. -adrenergic receptor
An iodinated photosensitive derivative of norepinephrine, N-(p-azido-m-iodophenethylamidoisobutyryl)norepinephrine (NAIN), has been synthesized and characterized. Carrier-free radioiodinated NAIN ((/sup 125/I)-NAIN) was used at 1-2 x 10/sup -9/ M to photoaffinity label the ..beta..-adrenergic receptor in guinea pig lung membranes. SDS-PAGE analysis of (-)-alprenolol (10/sup -5/M) protectable (/sup 125/I)-NAIN labeling showed the same molecular weight polypeptide (65 kDa) that was specifically derivatized with the antagonist photolabel, (/sup 125/I)-IABP. Specific labeling of the ..beta..-adrenergic receptor with (/sup 125/I)-NAIN was dependent on the presence of MgCl/sub 2/ and the absence of guanyl nucleotide. GTP..gamma..S (10/sup -4/ M) abolished specific receptor labeling by (/sup 125/I)-NAIN. N-ethylmaleimide (2 mm) in the presence of (/sup 125/I)-NAIN protected against the guanyl nucleotide effect. These data are consistent with photolabeling by (/sup 125/I)-NAIN while the agonist, receptor, and GTP binding protein are in a high affinity complex.
- Research Organization:
- Univ. of Wisconsin Medical School, Madison
- OSTI ID:
- 6078805
- Report Number(s):
- CONF-870644-; TRN: 87-037169
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
NORADRENALINE
CHEMICAL COMPOSITION
RECEPTORS
LABELLING
SYMPATHOMIMETICS
AFFINITY
CELL MEMBRANES
ELECTROPHORESIS
GUANYLIC ACID
GUINEA PIGS
IODINE 125
LUNGS
MOLECULAR WEIGHT
TRACER TECHNIQUES
ADRENAL HORMONES
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BODY
CARDIOTONICS
CARDIOVASCULAR AGENTS
CELL CONSTITUENTS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
NEUROREGULATORS
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIOISOTOPES
RESPIRATORY SYSTEM
RODENTS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques