TY - JOUR T1 - Discovery of Regulators of Receptor Internalization by High Throughput Flow Cytometry JF - Molecular Pharmacology JO - Mol Pharmacol DO - 10.1124/mol.112.079897 SP - mol.112.079897 AU - Yang Wu AU - Phillip Tapia AU - Gregory W. Fisher AU - Peter C Simons AU - J Jacob Strouse AU - Terry Foutz AU - Alan S Waggoner AU - Jonathan Jarvik AU - Larry A. Sklar Y1 - 2012/07/05 UR - http://molpharm.aspetjournals.org/content/early/2012/07/05/mol.112.079897.abstract N2 - We developed a platform combining fluorogen activating protein (FAP) technology with high-throughput flow cytometry to detect real-time protein trafficking to and from the plasma membrane in living cells. The hybrid platform allows drug discovery for trafficking receptors such as GPCRs, and has been validated using the β2 adrenergic receptor (β2AR) system. When a chemical library containing ~1,200 off-patent drugs was screened against cells expressing FAP-tagged β2AR, all 33 known β2AR active ligands in the library were successfully identified, together with a number of compounds that might regulate the receptor internalization in a non-traditional manner. Results indicate that the platform identifies ligands of target proteins regardless of the associated signaling pathway, which opens the door to the search for biased modulators of the receptor, and is also suitable for screening multiplexed targets for improved efficiency. The results revealed that ligands can be biased in the rate or the duration of receptor internalization, and that receptor internalization can be independent of the activation of the mitogen-activated protein kinase pathway. ER -