Structural basis of cooling agent and lipid sensing by the cold-activated TRPM8 channel

Abstract

Transient receptor potential melastatin member 8 (TRPM8) is a calcium ion (Ca2+)–permeable cation channel that serves as the primary cold and menthol sensor in humans. Activation of TRPM8 by cooling compounds relies on allosteric actions of agonist and membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2), but lack of structural information has thus far precluded a mechanistic understanding of ligand and lipid sensing by TRPM8. Using cryo–electron microscopy, we determined the structures of TRPM8 in complex with the synthetic cooling compound icilin, PIP2, and Ca2+, as well as in complex with the menthol analog WS-12 and PIP2. Our structures reveal the binding sites for cooling agonists and PIP2in TRPM8. Notably, PIP2binds to TRPM8 in two different modes, which illustrate the mechanism of allosteric coupling between PIP2and agonists. This study provides a platform for understanding the molecular mechanism of TRPM8 activation by cooling agents.

GemSpot: A Pipeline for Robust Modeling of Ligands into CryoEM Maps

“…In the example of the TRPM8 channel, the modeled pose for the ligand in 6NR3 41 agrees well with what we predicted by GlideEM, although this represents another example where docking without the EM map yields additional poses that fall elsewhere in the relatively large and open binding site. In contrast, the icilin/TRPM8 model in 6NR2 41 has significant strain energy in its ligand conformation.…”

“…Fubinaca/Cannabinoid receptor 1 (PDB:6N4B, EMD:0339) 33 ; GSK 3494245/Leishmania 20S proteasome (PDB:6QM7, EMD:4590) 36 ; Paromomycin/Leishmania ribosome (PDB:6AZ1, EMD:7024) 35 ; Menthol analogue WS-12/Ion channel TRPM8 (PDB:6NR2, EMD:0488) 41 ;…”

“…Icilin/Ion channel TRPM8 (PDB:6NR3, EMD:0487) 41 ; LY2119620/M2R (PDB:6OIK, EMD:20079) 38 ; Iperoxo/M2R (PDB:6OIK, EMD:20079) 38 ; Saxitoxin/Nav1.7 (PDB: 6J8G, EMD:9781) 39 ; Biculine/GABAA (PDB:6HUK, EMD:0280) 37 ; Xanax/GABAA (PDB:6HUO, EMD:0282) 37 ; Valium, GABAA (PDB:6HUP, EMD:0283) 37 ; NDI-091143/ATP Citrate Lyase (PDB:6O0H, EMD:0567) 7 ; paroxetine/serotonin transporter (PDB:6DZW, EMD:8941) 40 ;…”

Lipid Interactions of a Ciliary Membrane TRP Channel: Simulation and Structural Studies of Polycystin-2 (PC2)

“…Indirect inhibition of TRPV1 by PIP 2 in intact cells has also been reported (Thyagarajan et al, 2008). Recent cryoEM structures have revealed PIP 2 binding sites on TRPV5 (Hughes et al, 2018b), TRPML1 (Fine et al, 2018), and TRPM8 (Yin et al, 2019).…”

“…TRP channel mutations have been implicated in a number of different diseases (Nilius and Owsianik, 2010) and consequently are of interest as potential drug targets (Moran, 2018). Several TRP channels are modulated by membrane lipids (see for example (Fine et al, 2018;Wilkes et al, 2017;Yin et al, 2019), suggesting the possibility of lipid based therapies (Ciardo and Ferrer-Montiel, 2017).…”