Roth has made contributions to the fields of
G protein-coupled receptor (GPCR) pharmacology and neurobiology, particularly related to the function of
serotonin and
opioid receptors. His laboratory reported the structure of a
serotonin receptor bound to the hallucinogenic drug,
LSD. Other major works include identification of new probes and tools to detect GPCRs, obtained through directed evolution in animal cells, developing
receptors activated solely by a synthetic ligand (DREADDs), a
chemogenetic platform used to direct selective, dose-dependent activation of a specific G protein subtype in vivo.
Thomas Insel, then Director of NIMH, stated in 2014 that DREADDs were one of the most important breakthrough technologies for the NIH
BRAIN Initiative. and have been used by more than a thousand labs for interrogating neural circuits responsible for simple and complex behaviors in animals. == Awards and recognition ==