ABSTRACT
Almost every important molecular event in a cell takes place on the surface of biological membranes, and the membrane lipid composition has a great impact on how protein signaling complexes interact and function in the context of these membranes. In addition to the structural lipids, there is a class of phospholipids, the phosphoinositides, that are present in small amounts but show very rapid changes and high metabolic turnover. These lipids regulate a vast majority of cellular processes via interactions with peripheral or integral membrane proteins, and a plethora of synthesizing and metabolizing enzymes ensure tight temporal and spatial control over their changes. The highly localized and rapid changes in phosphoinositide levels demand experimental tools that are capable of detecting and following these changes, preferably in live cells. Moreover, to understand better the impact of phosphoinositide changes on any cellular process, it is also desirable to develop tools that allow for the artificial manipulation of these lipids with proper spatial and temporal control. This chapter briefly summarizes the developments that have fueled this field in recent years.
