Synthetic receptors imitate GPCRs

G protein-coupled receptors (GPCRs) are ubiquitous signaling proteins in the membranes of our cells. They’re involved in many physiological processes and are frequent drug targets. Researchers now report that a synthetic system that mimics GPCR signaling activity delivers druglike cargo when triggered by chemical cues. GPCRs lie in wait in cell membranes until signaling molecules such as hormones bind. These so-called first messengers turn on the GPCR, which then undergoes conformational changes that translate the exterior activation signal to the part of the receptor inside the cell. The receptor then activates G proteins that pass the signal through second messengers to targets inside the cell, turning on or off enzymes, ion channels, and other cell components. Last year, Nicholas H. Williams of the University of Sheffield, Christopher A. Hunter of the University of Cambridge, and coworkers designed artificial receptors that mimic GPCRs by transmitting signals from the outside to the