Evidence of glycosylated sites on the endothelin-1 receptor in Swiss 3T3 cells.
The effects of incubation of intact cells with six different lectins on the specific binding of [125I]endothelin-1 (ET-1) were determined in Swiss 3T3 fibroblasts. ET-1 binding was unaffected by pretreatment of cells for 1 h at 37 degrees C with concanavalin A, soybean agglutinin, Ulex europaeus agglutinin I, peanut agglutinin, or Galanthus nivalis agglutinin. However, preincubation of cells with 300 micrograms/ml of wheat germ agglutinin resulted in a 70% decrease in specific binding of ET-1 to cell-surface receptors. The inhibitory effects of wheat germ agglutinin were diminished by brief incubation of lectin-treated cells with 100 mM N-acetylglucosamine, a monosaccharide specifically recognized by wheat germ agglutinin. Neither glucose nor mannose had any effect on wheat germ agglutinin-mediated inhibition of the specific binding of ET-1. These results suggest that the ET-1 receptor on 3T3 cells is a glycoprotein that contains one or more N-acetylglucosamine residues at or near the ligand binding site.
Devesly
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P
Department of Pharmacology, Berlex Laboratories, Inc., Cedar Knolls, New Jersey.
Cade
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C
Polokoff
M A
MA
Botelho
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LH
D016475:3T3 Cells; D000117:Acetylglucosamine / Q000032:analysis; D000818:Animals; D016232:Endothelins / Q000378:metabolism*; D027801:Galanthus; D006023:Glycoproteins / Q000032:analysis; D037102:Lectins; D051379:Mice; D037121:Plant Lectins; D011956:Receptors, Cell Surface / Q000737:chemistry*; D017466:Receptors, Endothelin
D016232:Endothelins; D006023:Glycoproteins; D037102:Lectins; D037121:Plant Lectins; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D000117:Acetylglucosamine