Biomaterial Database

Affinity labeling of a cell surface receptor for epidermal growth factor. 1978

M Das, and T Miyakawa, and C F Fox

The membrane receptor for epidermal growth factor (EGF) on 3T3 cells has been identified and specifically labeled radiochemically using a photoreactive derivative of EGF. Photoreactive EGF, labeled with 125I, was incubated with 3T3 cells and then photolyzed in situ to generate a nitrene capable of reacting with a wide variety of chemical bonds. Analysis of the system by sodium dodecyl sulfate/polyacrylamide gel electrophoresis revealed, besides the band of EGF, only 1 other major radioactive band which migrated at approximately 190,000 daltons. This band was absent when a nonresponsive and nonbinding variant of 3T3 was used. A direct proportionality between binding activity and crosslinked complex formation was demonstrated using a variety of binding conditions. The crosslinked complex in intact cells is accessible to the action of a macromolecule like trypsin at 4 degrees, suggesting a cell surface location for this complex. Upon incubation of cells at 37 degrees, radioactivity from previously formed EGF-receptor crosslinked complex is converted by cellular action to 3 forms of mol wt less than or equal to 58,000 daltons. These are not accessible to trypsin action upon intact cells.

UI	MeSH Term	Description	Entries
D007097	Imines	Organic compounds containing a carbon-nitrogen double bond where a NITROGEN atom can be attached to HYDROGEN or an alkyl or aryl group.	Imine
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004815	Epidermal Growth Factor	A 6-kDa polypeptide growth factor initially discovered in mouse submaxillary glands. Human epidermal growth factor was originally isolated from urine based on its ability to inhibit gastric secretion and called urogastrone. Epidermal growth factor exerts a wide variety of biological effects including the promotion of proliferation and differentiation of mesenchymal and EPITHELIAL CELLS. It is synthesized as a transmembrane protein which can be cleaved to release a soluble active form.	EGF,Epidermal Growth Factor-Urogastrone,Urogastrone,Human Urinary Gastric Inhibitor,beta-Urogastrone,Growth Factor, Epidermal,Growth Factor-Urogastrone, Epidermal,beta Urogastrone
D000345	Affinity Labels	Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.	Affinity Labeling Reagents,Labeling Reagents, Affinity,Labels, Affinity,Reagents, Affinity Labeling
D001386	Azides	Organic or inorganic compounds that contain the -N3 group.	Azide
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures