ABSTRACT
This chapter describes the properties and applications of fluorescent probes for labeling organelles and subcellular compartments. It outlines some considerations appling to all these probes and then move on to descriptions of individual probes arranged according to their labeling targets. Probe concentration is axiomatic that biologically relevant image data must be independent of probe concentration. Labeling of the cytoplasm is required for measurement of cell volume and shape and for analysis of cellular migration and adhesion. Specific labeling of mitochondria in living cells is generated by electrophoretic uptake of cationic rhodamine, rosamine, and cyanine dyes driven by the respiration-coupled membrane potential. The Golgi apparatus is the primary site for post-synthetic glycosylation of proteins and lipids. This characteristic is exploited for targeting of both dye-based and FP-fusion labeling of this organelle. Nitrobenzoxadiazole (NBD) and BODIPY ceramides are biosynthetic precursors of glycosphingolipids. Incubation of live cells with NBD ceramide or BODIPY ceramide results in uptake and metabolic conversion to glycosphingolipids in the Golgi.
