9QHO | pdb_00009qho

Cryo-EM structure of mouse TRPM3 alpha 2 in complex with antagonist Primidone


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.28 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Starting Model: experimental
View more details

wwPDB Validation 3D Report Full Report

Validation slider image for 9QHO

This is version 1.1 of the entry. See complete history

Literature

Stereoselectivity and functional plasticity of a common ligand-binding pocket in TRPM3.

Bazeli, B.Shkumatov, A.V.Schenck, S.Vanherck, J.C.Janssens, A.Spieser, S.A.H.Marchand, D.Roelens, R.Chaltin, P.Marchand, A.Vriens, J.Voets, T.Brunner, J.D.

(2026) Nat Commun 17

  • DOI: https://doi.org/10.1038/s41467-026-71226-0
  • Primary Citation Related Structures: 
    9QHM, 9QHN, 9QHO, 9QHP, 9QHQ, 9T9U

  • PubMed Abstract: 

    The transient receptor potential melastatin 3 (TRPM3) channel is a key mediator of peripheral pain signaling, and pathogenic mutations in TRPM3 are linked to neurodevelopmental delay and epilepsy. Despite the therapeutic promise of TRPM3 modulators, the molecular mechanisms by which ligands modulate channel gating remain poorly understood. Here, we combine cryo-electron microscopy (cryo-EM) with functional analyses to characterize a promiscuous ligand-binding pocket formed by transmembrane helices S1-S4. This pocket accommodates several chemically diverse plant-derived and synthetic agonists and antagonists. We show stereoselectivity of TRPM3 for the (R)-enantiomer of the flavonoid antagonist isosakuranetin and the (R)-enantiomer of the synthetic agonist CIM0216. Mutations within this pocket-including variants identified in patients -alter ligand affinity and, in some cases, invert the functional outcome of ligand binding. These findings reveal the stereoselectivity and functional plasticity of the TRPM3 ligand-binding pocket, highlighting how subtle changes in the molecular interactions can produce divergent effects on channel gating, with important ramifications for TRPM3-targeted drug development and therapy.


  • Organizational Affiliation
    • Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Neuroscience, Leuven, Belgium, and Department of Molecular and Cellular Biology, KU Leuven, Leuven, Belgium.

Macromolecule Content 

  • Total Structure Weight: 653.72 kDa 
  • Atom Count: 28,360 
  • Modeled Residue Count: 3,432 
  • Deposited Residue Count: 5,636 
  • Unique protein chains: 1

Macromolecules

Find similar proteins by:|  3D Structure
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
MKIAA1616 protein
A, B, C, D
1,409Mus musculusMutation(s): 0 
Gene Names: Trpm3mKIAA1616
UniProt & NIH Common Fund Data Resources
Find proteins for Q69ZE8 (Mus musculus)
Explore Q69ZE8 
Go to UniProtKB:  Q69ZE8
IMPC:  MGI:2443101
Entity Groups
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ69ZE8
Sequence Annotations
Expand
Reference Sequence

Small Molecules

Ligands 3 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
PX8

Query on PX8



Download:Ideal Coordinates CCD File
G [auth B],
H [auth B],
K [auth C],
N [auth C]
1,2-DISTEAROYL-SN-GLYCERO-3-PHOSPHATE
C39 H76 O8 P
YFWHNAWEOZTIPI-DIPNUNPCSA-M
9Z9

Query on 9Z9



Download:Ideal Coordinates CCD File
E [auth A],
I [auth B],
L [auth C],
O [auth D]
(3beta,14beta,17beta,25R)-3-[4-methoxy-3-(methoxymethyl)butoxy]spirost-5-en
C34 H56 O5
CEEBZAXXSRFQIC-GZSGZGDASA-N
A1AIA
(Subject of Investigation/LOI)

Query on A1AIA



Download:Ideal Coordinates CCD File
F [auth A],
J [auth B],
M [auth C],
P [auth D]
primidone
C12 H14 N2 O2
DQMZLTXERSFNPB-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.28 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX1.21-5207
RECONSTRUCTIONcryoSPARC

Structure Validation

View Full Validation Report



Entry History 

& Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Not funded--

Revision History  (Full details and data files)

  • Version 1.0: 2026-02-11
    Type: Initial release
  • Version 1.1: 2026-08-26
    Changes: Data collection, Database references