Antipeptide antibody that specifically inhibits insulin receptor autophosphorylation and protein kinase activity
Two site-specific antibodies that immunoprecipitate the human insulin receptor have been prepared by immunizing rabbits with chemically synthesized peptides derived from the cDNA-predicted amino acid sequence of the ..beta.. subunit of the proreceptor. Antibodies to the carboxyl terminus (AbP5) and to a domain around tyrosine-960 (AbP4) specifically recognize the ..beta.. subunit of the receptor on immunoblots. Both antibodies immunoprecipitated /sup 125/I-labeled insulin-receptor complexes and the autophosphorylated receptor. Although neither antibody inhibited insulin binding to the receptor, both insulin-dependent autophosphorylation and exogenous substrate phosphorylation were inhibited by AbP4. Inhibition by AbP4 was dependent upon the phosphorylation state of the receptor; it was not detected when the receptor was autophosphorylated prior to addition of AbP4. AbP4 did not inhibit activity of the related epidermal growth factor (EGF)-receptor tyrosine protein kinase nor did it inhibit the activity of cAMP-dependent kinase or protein kinase C. The observation that an antibody directed to residues 952-967 of the proreceptor neutralizes the protein kinase activity of the ..beta.. subunit suggest that this region may play a critical role in the function of the hormone-dependent, protein tyrosine-specific kinase activity of the insulin receptor.
- Research Organization:
- Albert Einstein College of Medicine, Bronx, NY
- OSTI ID:
- 6390245
- Journal Information:
- Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 82:23
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
INSULIN
RECEPTORS
PHOSPHOTRANSFERASES
ENZYME ACTIVITY
PHOSPHORYLATION
AMINO ACID SEQUENCE
ANTIBODIES
BIOCHEMICAL REACTION KINETICS
HORMONES
IMMUNITY
IODINE 125
LABELLED COMPOUNDS
PEPTIDES
RABBITS
TRACER TECHNIQUES
TYROSINE
AMINO ACIDS
ANIMALS
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
HYDROXY ACIDS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MAMMALS
MEMBRANE PROTEINS
MOLECULAR STRUCTURE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PHOSPHORUS-GROUP TRANSFERASES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
TRANSFERASES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques