Fluorescence methods to probe nanometer-scale organization of molecules inliving cell membranes

The ability to study the structure and function of cell membranes and membr ane components is fundamental to understanding cellular processes. This req uires the use of methods which are capable of resolving structures at nanom eter-scale resolution in living cells. In this review we survey fluorescenc e imaging methodologies capable of nanometer-scale resolution. We then crit ically examine specific biological applications of these methods, in the co ntext of understanding membrane protein conformation and dynamics, intracel lular signaling, organization of lipid rafts, and cell surface topology.