Live cell imaging for studying g protein-coupled receptor activation in single cells.

G protein-coupled receptors (GPCRs) constitute the single largest family of target proteins for drugs of pain and anesthesia. Non-invasive assays based on the activity of G protein-based sensors in living cells allow the identification of potentially novel compounds for anesthesia and pain management with high specificity. Quantitative information about the efficacy of any molecule or drug compound that acts through a GPCR can be obtained through this approach. Furthermore, live cell assays provide spatio temporal information that is valuable in high content screening of compounds. Here, we describe the use of various fluorescently tagged G protein subunits and methods for using translocation and FRET-based G protein sensors in studying GPCR activation in living cells.