Glucocorticoid receptor transformation and DNA binding

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6438942

Tienrungroj, W

The overall goal is to probe the mechanism whereby glucocorticoid receptors are transformed from a non-DNA-binding form to their active DNA-binding form. The author has examined the effect of an endogenous inhibitor purified from rat liver cytosol on receptor binding to DNA. The inhibitor binds to transformed receptors in whole cytosol and prevent their binding to DNA. He also examined the role of sulfhydryl groups in determining the DNA binding activity of the transformed receptor and in determining the transformation process. Treatment of rat liver cytosol containing temperature-transformed, (/sup 3/H)dexamethasone-bound receptors at 0/sup 0/C with the sulfhydryl modifying reagent methyl methanethiosulfonate inhibits the DNA-binding activity of the receptor, and DNA-binding activity is restored after addition of dithiothreitol. In addition, he has examined the relationship between receptor phosphorylation and DNA binding. Untransformed receptor complexes purified from cytosol prepared from mouse L cells grown in medium containing (/sup 32/P)orthophosphate contain two components, a 100 k-Da and a 90-kDa subunit, both of which are phosphoproteins. On transformation, the receptor dissociates from the 90-kDa protein. Transformation of the complex under cell free conditions does not result in a dephosphorylation of the 100-kDa steroid-binding protein. Transformed receptor that has been bound to DNA and purified by monoclonal antibody is still in a phosphorylated form. These results suggest that dephosphorylation is not required for receptor binding to DNA.

• Research Organization: Michigan Univ., Ann Arbor (USA)
• OSTI ID: 6438942
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
CHEMICAL REACTIONS
CORTICOSTEROIDS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DNA
GLANDS
GLUCOCORTICOIDS
HORMONES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
KETONES
KINETICS
LABELLED COMPOUNDS
LIGHT NUCLEI
LIVER
MAMMALS
MEMBRANE PROTEINS
NUCLEI
NUCLEIC ACIDS
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS 32
PHOSPHORUS COMPOUNDS
PHOSPHORUS ISOTOPES
PHOSPHORYLATION
PREGNANES
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES