© 2002 Garland Science/Taylor & Francis Books
In this common pathway, activated phospholipase C-β hydrolyzes the inositide PI 4,5-bisphosphate to release diacylglyerol and inositol 1,4,5 trisphosphate. IP3 opens specific Ca2+ channels releasing the ions from the lumen of the endoplasmic reticulum. Diacylglycerol can be further cleaved to release arachidonic acid, a signaling molecule needed for the synthesis of other messengers such as prosta-glandins, or it can activate protein kinase C, a calcium-dependent kinase. (Adapted from B. Alberts et al.
Inside and out, cells teem with signaling activity. And inositides – particularly inositol phosphates and inositol lipids – are everywhere, mediating everything from ion-channel function to vesicle trafficking, apoptosis, cell growth, motility, and differentiation.1 Almost every cell uses one of the phosphoinositide signaling cascades: Receptors trigger the hydrolysis of the lipid phosphatidylinositol 4,5-bisphosphate to yield the second messengers, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol, which regulate intracellular ...
