Background |
Phosphoinositide-specific phospholipase C (PLC) plays a crucial role in the initiation of receptor mediated signal transduction through the generation of the two second messengers, inositol 1, 4, 5-triphosphate and diacylglycerol from phosphatidylinositol 4, 5-bisphosphate. There are many mammalian PLC isozymes, including PLC beta1, PLC beta2, PLC beta3, PLC beta4, PLC gamma1, PLC gamma2, PLC delta1, PLC delta2 and PLCepsilon. PLC gamma1 is widely distributed in bronchiolar epithelium, type I and II pneumocytes and fibroblasts of the interstitial tissue. Actin-regulatory protein Villin is tyrosine phosphorylated and associates with PLC gamma1 in the brush border of intestinal epithelial cells. Villin regulates PLC gamma1 activity by modifying its own ability to bind phosphatidylinositol 4, 5-biphosphate. PLC gamma1 binds Integrin alpha1/beta1 and modulates Integrin alpha1/beta-specific adhesion. PLC gamma1 and Ca2+ play a direct role in VEGF-regulated endothelial growth, however this signaling pathway is not linked to FGF-mediated effects in primary endothelial cells. PLC gamma1 is rapidly activated in response to growth factor stimulation and plays an important role in regulating cell proliferation and differentiation. It may also have a protective function during cellular response to oxidative stress. |