GPCR Signaling Assays

G protein-coupled receptors (GPCRs), also known as 7TM receptors, constitute the largest superfamily of cell surface receptors. These receptors play key roles in regulation of a wide variety of physiological processes, including cognition, metabolism, inflammation, immunity and cell proliferation, as well as development. As a result, GPCRs have been popular drug targets; 40% of approved drugs (or drugs currently on the market) directly target GPCRs. Despite the large number of GPCRs that are available as potential drug targets, currently approved drugs only address a small portion of the known receptors; many GPCRs remain uncharacterized. Thus, this target class remains an area of strong interest in drug discovery.

Methods to measure GPCRs come in many forms- In addition to measures of direct ligand binding, many are indirect assays that measure events proximal to binding the represent different signaling pathways- these include reporter assays, cAMP quantitation, β-Arrestin recruitment, IP3 measurements and calcium flux to name a few.