The ligand-induced phosphorylation of the platelet-derived growth factor (PDGF) receptor was followed at 37°C by a rapid dephosphorylation which was roughly parallel to the down regulation of the 125I-PDGF binding sites. At 4°C, when the ligand-receptor complexes remain associated with the cell surface, the phosphorylated form of the receptor was more stable. However if the ligand was dissociated from the receptor by means of a mild acid wash or a treatment with suramin, the dephosphorylation of the receptor also occurred at a low temperature. These data suggest that, due to the dissociation of the ligand, the kinase activity of the receptor is switched off so that the phosphotyrosine-containing receptors remain exposed to the action of phosphatases that rapidly dephosphorylate them
Dissociation of the ligand and dephosphorylation of the platelet-derived growth factor receptor
Morello L;
1988
Abstract
The ligand-induced phosphorylation of the platelet-derived growth factor (PDGF) receptor was followed at 37°C by a rapid dephosphorylation which was roughly parallel to the down regulation of the 125I-PDGF binding sites. At 4°C, when the ligand-receptor complexes remain associated with the cell surface, the phosphorylated form of the receptor was more stable. However if the ligand was dissociated from the receptor by means of a mild acid wash or a treatment with suramin, the dephosphorylation of the receptor also occurred at a low temperature. These data suggest that, due to the dissociation of the ligand, the kinase activity of the receptor is switched off so that the phosphotyrosine-containing receptors remain exposed to the action of phosphatases that rapidly dephosphorylate themI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
