Regulator of insulin receptor affinity in rat skeletal muscle sarcolemmal vesicles

Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6832560

Whitson, R H; Barnard, K J; Kaplan, S A; Itakura, K

Wheat germ agglutinin (WGA) affinity purification of detergent solubilized insulin receptors (IR) from rat skeletal muscle sarcolemmal vesicles resulted in an apparent increase in total insulin binding activity of greater than 5-fold, suggesting that an inhibitory component had been removed. This was verified when the flow-through fraction from the WGA column was dialyzed and added back to the partially purified receptor. The addition of a 100-fold dilution of the inhibitor preparation caused a 50% reduction in binding to trace amounts of /sup 125/I-insulin. Scatchard analysis revealed that the effect of the inhibitor was to decrease the affinity of the muscle IR. The inhibitor appeared to be tissue specific, inasmuch as the I/sub 50/'s for WGA-purified IR from rat fat and liver were 10 times the I/sub 50/ for muscle IR. The I/sub 50/ for insulin binding to intact IM-9 cells was 30 times the value for muscle IR. The inhibitor eluted in the void volume of Sephadex G-50 columns. Its activity was not destroyed by heating at 90/sup 0/C for 10 minutes, or by prolonged incubation with trypsin or dithiothreitol. The inhibitor described here may have a role in modulating insulin sensitivity in skeletal muscle.

• Research Organization: Beckman Research Institute of the City of Hope, Duarte, CA
• OSTI ID: 6832560
• Report Number(s): CONF-8606151-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
AGGLUTININS
ANIMAL CELLS
ANIMALS
ANTIBODIES
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
CHROMATOGRAPHY
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
ELECTRON CAPTURE RADIOISOTOPES
ENZYME INHIBITORS
FAT CELLS
FRACTIONATION
GEL PERMEATION CHROMATOGRAPHY
GLANDS
HORMONES
INSULIN
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIQUID COLUMN CHROMATOGRAPHY
LIVER
MAMMALS
MEMBRANE PROTEINS
MUSCLES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SEPARATION PROCESSES
SOMATIC CELLS
TRACER TECHNIQUES
VERTEBRATES