Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
Molecular Endocrinology
Year: 2009  |  Volume: 23  |  Issue: 7  |  Page No.: 1052 - 1064

Coordinate Regulation of Estrogen-Mediated Fibronectin Matrix Assembly and Epidermal Growth Factor Receptor Transactivation by the G Protein-Coupled Receptor, GPR30

J. A Quinn, C. T Graeber, A. R Frackelton, M Kim, J. E Schwarzbauer and E. J. Filardo    

Abstract:

Estrogen promotes changes in cytoskeletal architecture not easily attributed to the biological action of estrogen receptors, ER and ERβ. The Gs protein-coupled transmembrane receptor, GPR30, is linked to specific estrogen binding and rapid estrogen-mediated release of heparin-bound epidermal growth factor. Using marker rescue and dominant interfering mutant strategies, we show that estrogen action via GPR30 promotes fibronectin (FN) matrix assembly by human breast cancer cells. Stimulation with 17β-estradiol or the ER antagonist, ICI 182, 780, results in the recruitment of FN-engaged integrin 5β1 conformers to fibrillar adhesions and the synthesis of FN fibrils. Concurrent with this cellular response, GPR30 promotes the formation of Src-dependent, Shc-integrin 5β1 complexes. Function-blocking antibodies directed against integrin 5β1 or soluble Arg-Gly-Asp peptide fragments derived from FN specifically inhibited GPR30-mediated epidermal growth factor receptor transactivation. Estrogen-mediated FN matrix assembly and epidermal growth factor receptor transactivation were similarly disrupted in integrin β1-deficient GE11 cells, whereas reintroduction of integrin β1 into GE11 cells restored these responses. Mutant Shc (317Y/F) blocked GPR30-induced FN matrix assembly and tyrosyl phosphorylation of erbB1. Interestingly, relative to recombinant wild-type Shc, 317Y/F Shc was more readily retained in GPR30-induced integrin 5β1 complexes, yet this mutant did not prevent endogenous Shc-integrin 5β1 complex formation. Our results suggest that GPR30 coordinates estrogen-mediated FN matrix assembly and growth factor release in human breast cancer cells via a Shc-dependent signaling mechanism that activates integrin 5β1.

View Fulltext    |   Related Articles   |   Back
   
 
 
 
  Related Articles

No Article Found
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility