Equivalent molecular mass of cytosolic and nuclear forms of Ah receptor from Hepa-1 cells determined by photoaffinity labeling with 2,3,7,8-( sup 3 H)tetrachlorodibenzo-p-dioxin

Journal Article · Tue Oct 30 04:00:00 EST 1990 · Biochemical and Biophysical Research Communications; (USA)

DOI:https://doi.org/10.1016/0006-291X(90)90730-B· OSTI ID:6324722

Prokipcak, R D; Okey, A B ^[1]

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1. Univ. of Toronto, Ontario (Canada)

The structure of the Ah receptor previously has been extensively characterized by reversible binding of the high affinity ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin. We report the use of ({sup 3}H)2,3,7,8-tetrachlorodibenzo-p-dioxin as a photoaffinity ligand for Ah receptor from the mouse hepatoma cell line Hepa-1c1c9. Both cytosolic and nuclear forms of Ah receptor could be specifically photoaffinity-labeled, which allowed determination of molecular mass for the two forms under denaturing conditions. After analysis by fluorography of polyacrylamide gels run in the presence of sodium dodecyl sulfate, molecular mass for the cytosolic form of Ah receptor was estimated at 92,000 +/- 4,300 and that for the nuclear form was estimated at 93,500 +/- 3,400. Receptor in mixture of cytosol and nuclear extract (each labeled separately with ({sup 3}H)2,3,7,8-tetrachlorodibenzo-p-dioxin) migrated as a single band. These results are consistent with the presence of a common ligand-binding subunit of identical molecular mass in both cytosolic and nuclear complexes.

• OSTI ID: 6324722
• Journal Information: Biochemical and Biophysical Research Communications; (USA), Journal Name: Biochemical and Biophysical Research Communications; (USA) Vol. 172:2; ISSN BBRCA; ISSN 0006-291X
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
ANIMAL CELLS
ANIMALS
BIOCHEMICAL REACTION KINETICS
CELL CONSTITUENTS
CELL NUCLEI
DIOXIN
DISEASES
DRUGS
ELECTROPHORESIS
HEPATOMAS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LABELLING
LIGANDS
MAMMALS
MEMBRANE PROTEINS
MICE
MOLECULAR WEIGHT
NEOPLASMS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PROTEINS
REACTION KINETICS
RECEPTORS
RODENTS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TUMOR CELLS
VERTEBRATES