30ld | pdb_000030ld
Human Trpm4 with calcium and PBA at 37 degrees celsius
Structural highlights
DiseaseTRPM4_HUMAN Familial progressive cardiac conduction defect;Brugada syndrome. The disease is caused by mutations affecting the gene represented in this entry. FunctionTRPM4_HUMAN Calcium-activated non selective (CAN) cation channel that mediates membrane depolarization. While it is activated by increase in intracellular Ca(2+), it is impermeable to it. Mediates transport of monovalent cations (Na(+) > K(+) > Cs(+) > Li(+)), leading to depolarize the membrane. It thereby plays a central role in cadiomyocytes, neurons from entorhinal cortex, dorsal root and vomeronasal neurons, endocrine pancreas cells, kidney epithelial cells, cochlea hair cells etc. Participates in T-cell activation by modulating Ca(2+) oscillations after T lymphocyte activation, which is required for NFAT-dependent IL2 production. Involved in myogenic constriction of cerebral arteries. Controls insulin secretion in pancreatic beta-cells. May also be involved in pacemaking or could cause irregular electrical activity under conditions of Ca(2+) overload. Affects T-helper 1 (Th1) and T-helper 2 (Th2) cell motility and cytokine production through differential regulation of calcium signaling and NFATC1 localization. Enhances cell proliferation through up-regulation of the beta-catenin signaling pathway.[1] [2] [3] [4] [5] [6] [7] [8] Publication Abstract from PubMedTransient receptor potential melastatin 4 (TRPM4) is a Ca(2)(+)-activated cation channel whose pharmacology is shaped by its molecular environment. It remains poorly understood how temperature and membrane context influence inhibitor recognition. Here we combine cryo-electron microscopy of membrane-derived vesicles and detergent-solubilized TRPM4 to investigate lipid-associated architecture and binding of the potent anthranilic anilide inhibitor PBA. We find that membrane vesicles preserve a native-like paralipid environment and reveal lipid binding patterns highly similar to those observed in GDN, supporting detergent-solubilized TRPM4 as a structurally relevant system for ligand analysis. Strikingly, PBA occupies distinct binding pockets at 8 square degrees C and 37 square degrees C. At low temperature, PBA binds in a previously described inhibitor pocket formed by S3, S4, the S4-S5 linker and the TRP helix, whereas at physiological temperature it relocates to a distinct site within the S1-S4 domain proximal to the Ca(2)(+) regulatory region. These findings reveal temperature-dependent plasticity in TRPM4 ligand recognition. Temperature-dependent ligand relocation reveals plasticity of TRPM4 inhibition.,Schneiter D, Rougier JS, Abriel H, Stahlberg H, Ekundayo B bioRxiv [Preprint]. 2026 May 14:2026.05.13.724805. doi: , 10.64898/2026.05.13.724805. PMID:42182356[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
