scholarly journals Epidermal growth factor increases sn-1,2-diacylglycerol levels and activates phospholipase D-catalysed phosphatidylcholine breakdown in Swiss 3T3 cells in the absence of inositol-lipid hydrolysis

1992 ◽  
Vol 285 (1) ◽  
pp. 247-253 ◽  
Author(s):  
S J Cook ◽  
M J O Wakelam
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Phospholipase D ◽  
Egf Receptor ◽  
Kinase Inhibitor ◽  
3T3 Cells ◽  
Lipid Hydrolysis ◽  
Epidermal Growth ◽  
Swiss 3T3 ◽  
Pre Treatment

Addition of epidermal growth factor (EGF) to quiescent Swiss 3T3 cells resulted in a sustained increase in cellular diacylglycerol (DG) content in the absence of inositol-lipid hydrolysis. In the presence of non-cytotoxic concentrations of butan-1-ol, EGF stimulated the formation of phosphatidylbutanol, indicating that the EGF receptor was able to couple to the activation of phospholipase D (PLD). EGF-stimulated release of choline from Swiss 3T3 cells suggested that the major substrate for this PLD was phosphatidylcholine. Unlike bombesin-stimulated PLD activity, the response to EGF was not inhibited by a selective protein kinase C (PKC) inhibitor (Ro-31-8220), suggesting that it was not dependent on PKC activation. Pre-treatment of Swiss 3T3 cells with the EGF-receptor tyrosine kinase inhibitor AG18 selectively inhibited EGF-stimulated PLD activity; bombesin-stimulated PLD activity was unaffected. Butan-1-ol inhibited phorbol ester- and bombesin-stimulated DG formation suggesting a role for a coupled PLD/phosphatidate phosphohydrolase pathway; in contrast, EGF-stimulated DG formation was unaffected.

scholarly journals Activation of Endogenous Thrombin Receptors Causes Clustering and Sensitization of Epidermal Growth Factor Receptors of Swiss 3t3 Cells without Transactivation

2001 ◽  
Vol 152 (2) ◽  
pp. 263-274 ◽  
Author(s):  
Michael F. Crouch ◽  
Deborah A. Davy ◽  
Francis S. Willard ◽  
Leise A. Berven
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Thrombin Receptor ◽  
3T3 Cells ◽  
Downstream Effectors ◽  
Epidermal Growth ◽  
Swiss 3T3 ◽  
G Protein Coupled ◽  
Stimulation Of

The G protein–coupled thrombin receptor can induce cellular responses in some systems by transactivating the epidermal growth factor (EGF) receptor. This is in part due to the stimulation of ectoproteases that generate EGF receptor ligands. We show here that this cannot account for the stimulation of proliferation or migration by thrombin of Swiss 3T3 cells. Thrombin has no direct effect on the activation state of the EGF receptor or of its downstream effectors. However, thrombin induces the subcellular clustering of the EGF receptor at filamentous actin–containing structures at the leading edge and actin arcs of migrating cells in association with other signaling molecules, including Shc and phospholipase Cγ1. In these thrombin-primed cells, the subsequent migratory response to EGF is potentiated. Thrombin did not potentiate the EGF-stimulated EGF receptor phosphorylation. Thus, in Swiss 3T3 cells the G protein–coupled thrombin receptor can potentiate the EGF tyrosine kinase receptor response when activated by EGF, and this appears to be due to the subcellular concentration of the receptor with downstream effectors and not to the overall ability of EGF to induce receptor transphosphorylation. Thus, the EGF receptor subcellular localization which is altered by thrombin appears to be an important determinant of the efficacy of downstream EGF receptor signaling in cell migration.

scholarly journals Inhibition of the binding of 125I-labelled epidermal growth factor to mouse cells by a mitogen in goat mammary secretions

1983 ◽  
Vol 212 (2) ◽  
pp. 465-472 ◽  
Author(s):  
K D Brown ◽  
D M Blakeley
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Competitive Inhibitor ◽  
Inhibitory Effect ◽  
Temperature Sensitive ◽  
Egf Receptors ◽  
3T3 Cells ◽  
Epidermal Growth ◽  
Swiss 3T3

Pre-colostrum and colostrum from goats cause a marked inhibition of the binding of 125I-labelled epidermal growth factor (125I-EGF) to Swiss 3T3 cells. The ability of these secretions to inhibit 125I-EGF binding is closely correlated with the ability to stimulate DNA synthesis in quiescent 3T3 cell cultures, suggesting that goat mammary secretions may contain an EGF-related mitogen. However, the material in colostrum which inhibits 125I-EGF binding to Swiss 3T3 cells is a basic protein with Mr greater than 20000 and is thus quite different from mouse and human EGF. Furthermore, the colostral-mediated inhibition of 125I-EGF binding, although rapid and apparently competitive, differs from the inhibition of binding induced by native, unlabelled EGF. Thus, the inhibitory effect of colostrum is markedly decreased when the assay temperature is shifted from 37 degrees C to 4 degrees C whereas unlabelled EGF is an effective competitive inhibitor at both 37 degrees C and 4 degrees C. Incubation of cells with EGF causes a reduction in cell surface EGF receptors whereas exposure to colostrum does not induce down-regulation of the EGF receptor. Our results suggest that the colostral factor does not bind directly to EGF receptors but inhibits 125I-EGF binding by an indirect mechanism which involves a temperature-sensitive step.

scholarly journals Early events elicited by bombesin and structurally related peptides in quiescent Swiss 3T3 cells. I. Activation of protein kinase C and inhibition of epidermal growth factor binding.

1986 ◽  
Vol 102 (6) ◽  
pp. 2211-2222 ◽  
Author(s):  
I Zachary ◽  
J W Sinnett-Smith ◽  
E Rozengurt
Keyword(s):  
Protein Kinase C ◽  
Growth Factor ◽  
Protein Kinase ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Cellular Protein ◽  
3T3 Cells ◽  
Kinase C ◽  
Epidermal Growth ◽  
Swiss 3T3

Addition of bombesin to quiescent cultures of Swiss 3T3 cells caused a rapid increase in the phosphorylation of an Mr 80,000 cellular protein (designated 80k). The effect was both concentration and time dependent; enhancement in 80k phosphorylation could be detected as early as 10 s after the addition of peptide. Recently, a rapid increase in the phosphorylation of an 80k cellular protein after treatment with phorbol esters or diacylglycerol has been shown to reflect the activation of protein kinase C in intact fibroblasts (Rozengurt, E., A. Rodriguez-Pena, and K. A. Smith, 1983, Proc. Natl. Acad. Sci. USA., 80:7244-7248; Rozengurt, E., A. Rodriguez-Pena, M. Coombs, and J. Sinnett-Smith, 1984, Proc. Natl. Acad. Sci. USA., 81:5748-5752). The 80k phosphoproteins generated in response to bombesin and to phorbol 12,13-dibutyrate were identical as judged by one- and two-dimensional PAGE and by peptide mapping after partial proteolysis with Staphylococcus aureus V8 protease. In addition, prolonged pretreatment of 3T3 cells with phorbol 12,13-dibutyrate, which leads to the disappearance of protein kinase C activity, blocked the ability of bombesin to stimulate 80k. Bombesin also caused a rapid (1 min) inhibition of 125I-labeled epidermal growth factor (125I-EGF) binding to Swiss 3T3 cells. The inhibition was both concentration and temperature dependent and resulted from a marked decrease in the affinity of the EGF receptor for its ligand. Peptides structurally related to bombesin, including gastrin-releasing peptide, also stimulated 80k phosphorylation and inhibited 125I-EGF binding; both effects were selectively blocked by a novel bombesin antagonist. These results strongly suggest that these responses are mediated by specific high-affinity receptors that recognize the peptides of the bombesin family in Swiss 3T3 cells. While an increase in cytosolic Ca2+ concentration does not mediate the bombesin inhibition of 125I-EGF binding, the activation of protein kinase C in intact Swiss 3T3 cells by peptides of the bombesin family may lead to rapid inhibition of the binding of 125I-EGF to its cellular receptor.

947: Chemopreventive Effects of COX-2 Inhibitor and Epidermal Growth Factor (EGF)-Receptor Kinase Inhibitor on Rat Urinary Bladder Tumorigenesis

2004 ◽  
Vol 171 (4S) ◽  
pp. 251-251
Author(s):  
Kazunori Hattori ◽  
Katsuyuki Iida ◽  
Akira Johraku ◽  
Sadamu Tsukamoto ◽  
Taeko Asano ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Urinary Bladder ◽  
Egf Receptor ◽  
Kinase Inhibitor ◽  
Receptor Kinase ◽  
Rat Urinary Bladder ◽  
Epidermal Growth ◽  
Cox 2

scholarly journals Epidermal growth factor-induced phosphoinositide hydrolysis in permeabilized 3T3 cells: lack of guanosine triphosphate dependence and inhibition by tyrosine-containing peptides.

1990 ◽  
Vol 1 (9) ◽  
pp. 615-620 ◽  
Author(s):  
G F Verheijden ◽  
I Verlaan ◽  
J Schlessinger ◽  
W H Moolenaar
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
G Protein ◽  
Egf Receptor ◽  
Phosphoinositide Hydrolysis ◽  
3T3 Cells ◽  
Guanosine Triphosphate ◽  
Intact Cells ◽  
Epidermal Growth ◽  
Gamma S

The possible involvement of a stimulatory guanosine triphosphate (GTP)-binding (G) protein in epidermal growth factor (EGF)-induced phosphoinositide hydrolysis has been investigated in permeabilized NIH-3T3 cells expressing the human EGF receptor. The mitogenic phospholipid lysophosphatidate (LPA), a potent inducer of phosphoinositide hydrolysis, was used as a control stimulus. In intact cells, pertussis toxin partially inhibits the LPA-induced formation of inositol phosphates, but has no effect on the response to EGF. In cells permeabilized with streptolysin-O, guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) dramatically increases the initial rate of inositol phosphate formation induced by LPA. In contrast, activation of phospholipase C (PLC) by EGF occurs in a GTP-independent manner. Guanine 5'-O-(2-thiodiphosphate) (GDP beta S) which keeps G proteins in their inactive state, blocks the stimulation by LPA and GTP gamma S, but fails to affect the EGF-induced response. Tyrosine-containing substrate peptides, when added to permeabilized cells, inhibit EGF-induced phosphoinositide hydrolysis without interfering with the response to LPA and GTP gamma S. These data suggest that the EGF receptor does not utilize an intermediary G protein to activate PLC and that receptor-mediated activation of effector systems can be inhibited by exogenous substrate peptides.

Epidermal growth factor and bombesin differ strikingly in the induction of early responses in Swiss 3T3 cells

1990 ◽  
Vol 142 (3) ◽  
pp. 441-448 ◽  
Author(s):  
Arjo J. Bierman ◽  
Leo Koenderman ◽  
Anton J. Tool ◽  
W. De Laat Siegfried
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
3T3 Cells ◽  
Epidermal Growth ◽  
Swiss 3T3

scholarly journals Chicken epidermal growth factor (EGF) receptor: cDNA cloning, expression in mouse cells, and differential binding of EGF and transforming growth factor alpha.

1988 ◽  
Vol 8 (5) ◽  
pp. 1970-1978 ◽  
Author(s):  
I Lax ◽  
A Johnson ◽  
R Howk ◽  
J Sap ◽  
F Bellot ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Alpha ◽  
3T3 Cells ◽  
Epidermal Growth ◽  
Factor Alpha ◽  
Differential Binding ◽  
Nih 3T3

The primary structure of the chicken epidermal growth factor (EGF) receptor was deduced from the sequence of a cDNA clone containing the complete coding sequence and shown to be highly homologous to the human EGF receptor. NIH-3T3 cells devoid of endogenous EGF receptor were transfected with the appropriate cDNA constructs and shown to express either chicken or human EGF receptors. Like the human EGF receptor, the chicken EGF receptor is a glycoprotein with an apparent molecular weight of 170,000. Murine EGF bound to the chicken receptor with approximately 100-fold lower affinity than to the human receptor molecule. Surprisingly, human transforming growth factor alpha (TGF-alpha) bound equally well or even better to the chicken EGF receptor than to the human EGF receptor. Moreover, TGF-alpha stimulated DNA synthesis 100-fold better than did EGF in NIH 3T3 cells that expressed the chicken EGF receptor. The differential binding and potency of mammalian EGF and TGF-alpha by the avian EGF receptor contrasts with the similar affinities of the mammalian receptor for the two growth factors.

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