This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by DePalo, L. Articles by Das, M. Search for Related Content PubMed PubMed Citation Articles by DePalo, L. Articles by Das, M.

Epidermal Growth Factor-induced Stimulation of Epidermal Growth Factor-Receptor Synthesis in Human Cytotrophoblasts and A431 Carcinoma Cells¹

Department of Biochemistry and Biophysics, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania 19104

Epidermal growth factor (EGF)-receptor is a transmembrane glycoprotein whose intracellular degradation is known to be enhanced by EGF. We tested whether the receptor is replenished during this process by an enhanced rate of synthesis. Human A431 epidermoid carcinoma cells and primary cultures of human placental cytotrophoblasts were used in these studies. Cells were labeled with [³⁵S]methionine, and EGF-receptor biosynthesis was quantitated by immunoprecipitation using a monoclonal anti-EGF-receptor antibody. EGF stimulated receptor biosynthesis at concentrations of 0.1 to 1 nM. The effect was seen within 2 h of EGF addition. At high EGF concentrations the stimulatory effect was diminished. In contrast, the effect of EGF on receptor degradation in these cells was negligible at low nanomolar concentrations and was pronounced only at saturating concentrations ( 10 nM). These results show that occupation of the cell surface EGF-receptor by its ligand can lead to the production of more receptor protein, thus counterbalancing the negative effect on receptor degradation. At low nanomolar concentrations of EGF the stimulatory effect on receptor synthesis predominates over degradation, indicating a positive regulatory role of EGF in receptor action.

¹ This work was supported by NIH Grants CA-43787 and CA-15822.

² Present address: Cardiovascular Pulmonary Division, Hospital of the University of Pennsylvania, Philadelphia, PA 19104.

³ To whom requests for reprints should be addressed.

Received 9/ 9/87. Revised 11/23/87. Accepted 12/ 2/87.

This article has been cited by other articles:

				V.H.W. Dissanayake, C. Tower, A. Broderick, L.J. Stocker, H.R. Seneviratne, R.W. Jayasekara, N. Kalsheker, F.B. Pipkin, and L. Morgan Polymorphism in the epidermal growth factor gene is associated with birthweight in Sinhalese and white Western Europeans Mol. Hum. Reprod., June 1, 2007; 13(6): 425 - 429. [Abstract] [Full Text] [PDF]

				M. Silvy, P.-M. Martin, N. Chajry, and Y. Berthois Differential Dose-Dependent Effects of Epidermal Growth Factor on Gene Expression in A431 Cells: Evidence for a Signal Transduction Pathway That Can Bypass Raf-1 Activation Endocrinology, May 1, 1998; 139(5): 2382 - 2391. [Abstract] [Full Text] [PDF]

				C Rebut-Bonneton, S Boutemy-Roulier, and D Evain-Brion Modulation of pp60c-src activity and cellular localization during differentiation of human trophoblast cells in culture J. Cell Sci., January 7, 1993; 105(3): 629 - 636. [Abstract] [PDF]