Abstract
Cholesterol is one of the major membrane constituent of eukaryotic cell membranes, where it performs multiple important functions; moreover it is involved in lipid raft formation. Cholesterol is not detectable on its own, e.g. it is not a fluorophore.
Therefore it is possible to visualize cholesterol for studying its distribution and localization in cells with fluorescent reporter molecules. They can be classified either as cholesterol specific binding probes (cholesteroloxidases, macrolide filipin, cytolysins), or cholesterol analogs (dehydroergosterol, cholestatrienol, NBD-cholesterol, BODIPY-cholesterol).
Progress in cholesterol research is linked to development and use of appropriate analogs, which closely mimic properties of cholesterol, or probes, which do not affect cell physiology.