The α5β1 integrin selectively enhances epidermal growth factor signaling to the phosphatidylinositol-3-kinase/Akt pathway in intestinal epithelial cells

• Published in: Biochimica et biophysica acta. Molecular cell research Vol. 1542; no. 1-3; pp. 23 - 31
• Main Authors: Lee, Jung Weon, Juliano, R.L.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.01.2002
• Subjects: Akt/PKB; Epidermal growth factor receptor; Integrin; Phosphatidylinositol-3-kinase; Signaling; Phosphatidylinositol-3-kinase; Signaling; p85, 85 kDa subunit of PI-3-kinase; RIE, rat intestinal epithelial cells; Integrin; MAP kinase, mitogen activated protein kinase; Akt/PKB; RTK, receptor tyrosine kinase; PI-3-kinase, phosphatidylinositol-3-kinase; EGFR, epidermal growth factor receptor; Epidermal growth factor receptor
• ISSN: 0167-4889; 1879-2596
• DOI: 10.1016/S0167-4889(01)00161-6

We have investigated EGF-driven signaling processes in rat intestinal epithelial cell lines that overexpress either the α5β1 integrin or the α2β1 integrin. Both cell types display efficient activation of Erk/MAP kinase, but only the α5β1 expressing cells display a strong activation of Akt. A complex is formed between activated EGFR and α5β1, but not with α2β1; this complex also contains ErbB3 and p85. Thus α5β1 can support efficient activation of both the Erk and the phosphatidylinositol-3-kinase/Akt branches of the EGFR signaling cascade, whereas α2β1 can support only the Erk branch.