| Autor: |
Bearz, A., Tell, G., Formisano, S., Merluzzi, S., Colombatti, A., Pucillo, C. |
| Předmět: |
|
| Zdroj: |
Immunology; Dec99, Vol. 98 Issue 4, p564-568, 5p, 3 Black and White Photographs, 3 Diagrams |
| Abstrakt: |
Summary The β1 integrins are a family of heterodimeric adhesion receptors involved in cell‐to‐cell contacts and cell‐to‐extracellular matrix interactions. Through their adhesive role, integrins participate in transduction of outside/inside signals and contribute to trigger a multitude of cellular events such as differentiation, cell activation, and motility. The fibronectin integrin receptors, α4 β1 and α5 β1 , can function as costimulatory molecules in T‐cell receptor (TCR)‐dependent T‐cell activation. In the current study the Jurkat T‐cell line was used as a model system to investigate the TCR‐independent role of cell adhesion to fibronectin in the activation of Zap‐70, a central molecule in the signalling events in T cells. Upon adhesion to plastic immobilized fibronectin but not to bovine serum albumin (BSA) the phosphorylation of p125FAK , a protein kinase that localizes to focal adhesion sites, was induced. Moreover, clustering of fibronectin receptors led to the detection of a p125FAK /Zap‐70 complex. Finally, while the complex between fak‐B, another protein kinase localized to focal adhesion sites, and Zap‐70 was detected in cells plated either on BSA or on fibronectin, the formation of the p125FAK /Zap‐70 complex appeared specifically induced following fibronectin‐mediated integrin clustering. These data suggest the existence of a high degree of specificity when the members of the β1 integrin family mediate signalling pathways in T cells. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
