EurekaMag.com logo
+ Site Statistics
References:
53,214,146
Abstracts:
29,074,682
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Regulation of high affinity and low affinity epidermal growth factor receptors by glucocorticoids


Archives of Biochemistry & Biophysics 235(1): 141-149
Regulation of high affinity and low affinity epidermal growth factor receptors by glucocorticoids
Receptors for epidermal growth factor (EGF) in HeLa S3 cells exist in 2 forms, which differ in both affinity and capacity. Both the number of receptors and their distribution into low- and high-affinity forms are modulated by glucocorticoids. Scatchard analysis of saturation binding assays performed at 0.degree. C indicates that there is a low-affinity class of receptors (Kd .simeq. 1.5 nM), which contains .apprx. 6 .times. 104 binding sites per cell, and a 2nd, high-affinity class of receptors (Kd .simeq. 0.16 nM) containing .apprx. 5 .times. 103 binding sites per cell. Exposure of HeLa S3 cells to 10-7 M dexamethasone for 24 h increased EGF binding to whole cells by increasing the numbers of low- and high-affinity receptors by 20 and 114%, respectively. The increase in EGF binding depends upon the dose of dexamethasone, being raised from 10-11 to 10-6 M. EGF binding is half-maximal near 2-4 .times. 10-9 M, a concentration equal to the Kd of dexamethasone for the glucocorticoid receptor in these cells. The increase in EGF binding is specific for glucocorticoids, occurring when the HeLa S3 cells are exposed to 10-7 M cortisol or dexamethasone for 24 h, but not when the cells are similarly treated with testosterone, 5.alpha.-dihydroxytestosterone, 17.beta.-estradiol or progesterone. The effect on EGF binding appears to be biphasic; the initial rapid increase occurs between 8 and 12 h, is blocked by both 10-6 M cyclohexamide and 0.1 .mu.g/ml actinomycin D, and is followed by a more gradual increase thereafter. These data indicate that glucocorticoids are able to regulate both the number of EGF receptors and their distribution into high- and low-affinity components.

(PDF 0-2 workdays service: $29.90)

Accession: 006288461



Related references

Regulation of high- and low-affinity epidermal growth factor receptors by glucocorticoids. Archives of Biochemistry and Biophysics 235(1): 141-149, 1984

Association of iodine 125 labeled nerve growth factor with pc 12 pheochromocytoma cells evidence for internalization via high affinity receptors only and for long term regulation by nerve growth factor of both high affinity and low affinity receptors. Journal of Biological Chemistry 259(24): 15509-15516, 1984

Molecular basis for the origin of high affinity epidermal growth factor binding in cultured cells effect of 12 o tetradecanoyl phorbol 13 acetate on the generation of high affinity epidermal growth factor receptors in balb c 313 cells and isolated membranes. Journal of Supramolecular Structure & Cellular Biochemistry (SUPPL 5): 159, 1981

Resolution of high and low affinity epidermal growth factor receptors. Inhibition of high affinity component by low temperature, cycloheximide, and phorbol esters. Journal of Biological Chemistry 257(6): 3053-3060, 1982

Association of 125I-nerve growth factor with PC12 pheochromocytoma cells. Evidence for internalization via high-affinity receptors only and for long-term regulation by nerve growth factor of both high- and low-affinity receptors. Journal of Biological Chemistry 259(24): 15509-15516, 1984

Mitogenic response to epidermal growth factor relationship to number affinity and down regulation of epidermal growth factor receptors in 3 murine embryo cell lines. Journal of Supramolecular Structure 9(1): 41-46, 1978

Growth stimulation of A431 cells by epidermal growth factor: identification of high-affinity receptors for epidermal growth factor by an anti-receptor monoclonal antibody. Proceedings of the National Academy of Sciences of the United States of America 80(5): 1337-1341, 1983

Regulation of surface expression of high-affinity receptors for epidermal growth factor (EGF) in hepatocytes by hormones, differentiating agents, and phorbol ester. Digestive Diseases and Sciences 37(2): 233-239, 1992

Inverse relationship between epidermal growth factor induced proliferation and expression of high affinity surface epidermal growth factor receptors in rat hepatocytes. Laboratory Investigation; A Journal of Technical Methods and Pathology 60(2): 254-259, 1989

Resolution of high and low affinity epidermal growth factor receptors. Journal of Cellular Biochemistry Supplement (6): 169, 1982