Structural insights into TRPV2 activation by small molecules

Abstract

Transient receptor potential vanilloid 2 (TRPV2) is involved in many critical physiological and pathophysiological processes, making it a promising drug target. Here we present cryo-electron microscopy (cryo-EM) structures of rat TRPV2 in lipid nanodiscs activated by 2-aminoethoxydiphenyl borate (2-APB) and propose a TRPV2-specific 2-ABP binding site at the interface of S5 of one monomer and the S4-S5 linker of the adjacent monomer. In silico docking and electrophysiological studies confirm the key role of His521 and Arg539 in 2-APB activation of TRPV2. Additionally, electrophysiological experiments show that the combination of 2-APB and cannabidiol has a synergetic effect on TRPV2 activation, and cryo-EM structures demonstrate that both drugs were able to bind simultaneously. Together, our cryo-EM structures represent multiple functional states of the channel, providing a native picture of TRPV2 activation by small molecules and a structural framework for the development of TRPV2-specific activators.

Cannabinoid non-cannabidiol site modulation of TRPV2 structure and function

“…Thus, both compounds need to be present for a synergistic effect on TRPV2. A synergistic activation of heterologously expressed TRPV2 has also been shown for 2-APB in combination with probenecid 39 or CBD 29 as well as 2-APB and oxidants 7 . Whether C16 acts synergistically with 2-APB, CBD or oxidants and how its gating mechanism is related to the heat activation pathway are topics for future studies.…”

“…Together, this could indicate that the transient response to probenecid is dependent on extracellular Ca 2+ and involves an activation mechanism distinct from that of 2-APB. However, transient responses are also observed for 2-APB and CBD at higher concentrations, visible just before washout, in Ca 2+ -free recording solutions 29 . Perhaps, the strength and duration of the stimulus also contribute to the transient responses, reflecting different conformational states of the channel.…”

“…The first high-resolution structures of TRPV1 22 using cryo-EM paved the way for understanding how polymodal TRP channels are gated at a near atom level, and many cryo-EM structures of TRPV channels, including TRPV2, are now available 21,[23][24][25] . Importantly, recent cryo-EM studies of TRPV2 have proposed ligand binding sites for both activators such as cannabidiol (CBD), resiniferatoxin (RTX), and 2-APB as well as the inhibitor piperlongumine (PLG) [26][27][28][29][30] .…”

Modulation of TRPV2 by endogenous and exogenous ligands: A computational study

“…In TRP channels, ligand binding sites often overlap with lipid binding pockets. 1,4,16,18,23,33,39,43 Competition between endogenous lipids and exogenous ligands is common in TRP channel activation/inhibition mechanisms. 18,23,38,39,47 We also elucidated the dynamics of structural lipids and CBD, as well as the modulation exerted by them.…”

“…1,4,16,18,23,33,39,43 Competition between endogenous lipids and exogenous ligands is common in TRP channel activation/inhibition mechanisms. 18,23,38,39,47 We also elucidated the dynamics of structural lipids and CBD, as well as the modulation exerted by them. Our simulation results of VSLD and vanilloid lipids clearly demonstrate such a role as wedges in the helix bundle, and further distinguish the cooperative wedge (VSLD lipid) from a non-cooperative one (vanilloid lipid).…”