Effect of epidermal growth factor on phosphatidylinositol 3-kinase activity in rabbit corneal epithelial cells

Experimental Eye Research
Y Zhang, R A Akhtar

Abstract

We investigated the effect of epidermal growth factor (EGF) on phosphatidylinositol 3-kinase (PI 3-kinase) activity in SV-40 transformed rabbit corneal epithelial cells (RCEC) and in normal corneal epithelial cells grown in primary culture. The enzyme products, 3-phosphorylated phosphoinositides, were identified by TLC and by deacylation followed by separation on HPLC. Addition of 30 ng ml-1 EGF to 32P-labeled SV-40 transformed or primary epithelial cell culture, increased the radioactivity in phosphatidylinositol 3,4,5-trisphosphate (PIP3) by about 96% over that of control incubations. The growth factor also significantly increased the radioactivity in phosphatidylinositol 4-phosphate [PI(4)P], phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and phosphatidic acid which was quite similar in the two cell types. The EGF-mediated increase in PIP3 formation in RCEC was dose- and time-dependent. Treatment of RCEC lysate with anti-PI 3-kinase antibody immunoprecipitated proteins that phosphorylated PI, PI(4)P and PI(4,5)P2 to corresponding 3-phosphorylated phosphoinositides. Incubation of RCEC with EGF resulted in a dose- and time-dependent increase in PI 3-kinase activity associated with the immunoprecipitate. Nonionic detergent, ...Continue Reading

Citations

Feb 8, 2007·Journal of Cell Science·Jia YinFu-Shin X Yu
Nov 24, 2007·Seminars in Cell & Developmental Biology·P S Zelenka, P Arpitha
Jul 11, 2001·Experimental Biology and Medicine·L LuW W Kao

❮ Previous
Next ❯

Related Concepts

Related Feeds

AKT Pathway

This feed focuses on the AKT serine/threonine kinase, which is an important signaling pathway involved in processes such as glucose metabolism and cell survival.