Cross-linking of epidermal growth factor receptors in intact cells: detection of initial stages of receptor clustering and determination of molecular weight of high-affinity receptors

Journal Article · Tue Oct 21 00:00:00 EDT 1986 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00369a011· OSTI ID:6523674

Fanger, B O; Austin, K S; Earp, H S; Cidlowski, J A

A method was developed to label epidermal growth factor (EGF) receptors with /sup 125/I-EGF in whole cells using chemical cross-linking reagents. Polyacrylamide gel electrophoresis resolved an M/sub r/ approx. 180,000 EGF-receptor complex and larger M/sub r/ greater than or equal to 360,000 aggregates. The formation of the larger complexes was timed and temperature dependent and appeared to represent the initial events of EGF receptor clustering. Alteration of the ratio of /sup 125/I-EGF-labeled high- and low- affinity complexes by competition with unlabeled EGF or by induction of additional high-affinity sites with dexamethasone suggested that both sites were represented by the M/sub r/ approx. 180,000 /sup 125/I-EGF-receptor complexes. Digestion of cells before cross-linking detected a small population of trypsin-resistant M/sub r/ approx. 180,000 receptors, which could represent previously described cryptic and/or high-affinity receptors. Few of the M/sub r/ approx. 360,000 receptors were trypsin resistant. Glucocorticoid induction of high-affinity EGF receptors failed to induce detectable changes in the microclustering of EGF receptors but did result in a 50% increase in EGF-induced receptor phosphorylation in HeLa S/sub 3/ cell membranes at 4/sup 0/C. Thus, glucocorticoids increase high-affinity EGF binding sites, EGF-induced receptor phosphorylation, and cell growth.

• Research Organization: Univ. of North Carolina, Chapel Hill
• OSTI ID: 6523674
• Journal Information: Biochemistry; (United States), Vol. 25:21
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
59 BASIC BIOLOGICAL SCIENCES
HELA CELLS
AUTORADIOGRAPHY
RECEPTORS
CROSS-LINKING
MOLECULAR STRUCTURE
MOLECULAR WEIGHT
ATP
DEXAMETHASONE
ELECTROPHORESIS
EPIDERMIS
GLUCOCORTICOIDS
GROWTH
IODINE 125
PHOSPHORUS 32
PHOSPHORYLATION
ADRENAL HORMONES
ANIMAL TISSUES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CHEMICAL REACTIONS
CORTICOSTEROIDS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
EPITHELIUM
HORMONES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
KETONES
LIGHT NUCLEI
MEMBRANE PROTEINS
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PHOSPHORUS ISOTOPES
POLYMERIZATION
PREGNANES
PROTEINS
RADIOISOTOPES
SKIN
STEROID HORMONES
STEROIDS
TISSUES
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