A group at RIKEN has tracked the movement of nine types of fluorescently labeled G protein-coupled receptors (GPLC) in living cultured HEK 293 cells using a total internal reflection fluorescence microscope. It turned out that movement of nine kinds of GPCRs became slow when they were activated by drugs. In addition, the relationship between receptor movement and function in a metabotropic glutamate receptor (mGluR) was analyzed in detail by two-color simultaneous single molecule imaging. As a result, it was revealed that many of the receptors interacting with G protein were fast moving, whereas receptors interacting with clathrin stopped moving. It is expected that such procedures may help to study drug efficacy on a single-molecule level.

RIKEN news release, September 19, 2018