Reconstitution of Epidermal Growth Factor Receptor Transmodulation by Platelet-derived Growth Factor in Chinese Hamster Ovary Cells

• Published in: The Journal of biological chemistry 1989-08, Vol.264 (23), p.13642-13647
• Main Authors: Countaway, J L, Gironès, N, Davis, R J
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cell Line; Cell physiology; Cricetinae; Cricetulus; DNA - genetics; DNA Replication; ErbB Receptors - drug effects; ErbB Receptors - genetics; ErbB Receptors - metabolism; Female; Fundamental and applied biological sciences. Psychology; Humans; Kinetics; Molecular and cellular biology; Ovary; Platelet-Derived Growth Factor - pharmacology; Protein Kinase C - metabolism; Receptors, Cell Surface - metabolism; Receptors, Platelet-Derived Growth Factor; Responses to growth factors, tumor promotors, other factors; Tetradecanoylphorbol Acetate - pharmacology; Transfection
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)80045-X

Platelet-derived growth factor (PDGF) causes an acute decrease in the high affinity binding of epidermal growth factor (EGF) to cell surface receptors and an increase in the phosphorylation state of the EGF receptor at threonine654. The hypothesis that PDGF action to regulate the EGF receptor is mediated by the activation of protein kinase C and the subsequent phosphorylation of EGF receptor threonine654 was tested. The human receptors for PDGF and EGF were expressed in Chinese hamster ovary cells that lack expression of endogenous receptors for these growth factors. The heterologous regulation of the EGF receptor by PDGF was reconstituted in cells expressing [Thr654]EGF receptors or [Ala654]EGF receptors. PDGF action was also observed in phorbol ester down-regulated cells that lack detectable protein kinase C activity. Together these data indicate that neither protein kinase C nor the phosphorylation of EGF receptor threonine654 is required for the regulation of the apparent affinity of the EGF receptor by PDGF.