Epitope tagged α2-AR subtypes have been used to address a variety of cell biological questions, and the strategies used are readily applicable to all GPCR as well as other cell surface proteins. We have provided detailed protocols for successful utilization of the epitope-tagged receptor in the studies of protein localization and trafficking in epithelial cells, and the mechanisms by which this is achieved. We have also described reversible biotinytion strategies to examine agonist-dependent (and independent) receptor turnover at the cell surface.