Molecular mechanism of TRPV2 channel modulation by cannabidiol
Transient receptor potential vanilloid 2 (TRPV2) plays a critical role in neuronal development, cardiac function, immunity, and cancer. Cannabidiol (CBD), the non-psychotropic therapeutically active ingredient of Cannabis sativa, is a potent activator of TRPV2 and also modulates other transient receptor potential (TRP) channels. Here, we determined structures of the full-length TRPV2 channel in a CBD-bound state in detergent and in PI(4,5)P2 enriched nanodiscs by cryo-electron microscopy. CBD interacts with TRPV2 through a hydrophobic pocket located between S5 and S6 helices of adjacent subunits, which differs from known ligand and lipid binding sites in other TRP channels. Comparison between apo- and two CBD-bound TRPV2 structures reveals that the S4-S5 linker plays a critical role in channel gating upon CBD binding. The TRPV2 \"vanilloid\" pocket, which is critical for ligand-dependent gating in other TRPV channels, stays unoccupied by annular lipids, PI(4,5)P2, or CBD. Together these results provide a foundation to further understand TRPV channel gating properties and their divergent physiological functions and to accelerate structure-based drug design.