+Open data
-Basic information
Entry | Database: PDB / ID: 7tcp | ||||||
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Title | Structure of Xenopus KCNQ1-CaM | ||||||
Components |
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Keywords | TRANSPORT PROTEIN / ion channel | ||||||
Function / homology | Function and homology information regulation of gastric acid secretion / membrane repolarization / delayed rectifier potassium channel activity / outward rectifier potassium channel activity / intestinal absorption / CaM pathway / Cam-PDE 1 activation / Sodium/Calcium exchangers / Calmodulin induced events / Reduction of cytosolic Ca++ levels ...regulation of gastric acid secretion / membrane repolarization / delayed rectifier potassium channel activity / outward rectifier potassium channel activity / intestinal absorption / CaM pathway / Cam-PDE 1 activation / Sodium/Calcium exchangers / Calmodulin induced events / Reduction of cytosolic Ca++ levels / CREB1 phosphorylation through the activation of CaMKII/CaMKK/CaMKIV cascasde / Activation of Ca-permeable Kainate Receptor / Loss of phosphorylation of MECP2 at T308 / CREB1 phosphorylation through the activation of Adenylate Cyclase / PKA activation / negative regulation of high voltage-gated calcium channel activity / monoatomic ion channel complex / CaMK IV-mediated phosphorylation of CREB / Glycogen breakdown (glycogenolysis) / positive regulation of cyclic-nucleotide phosphodiesterase activity / organelle localization by membrane tethering / negative regulation of calcium ion export across plasma membrane / autophagosome membrane docking / mitochondrion-endoplasmic reticulum membrane tethering / CLEC7A (Dectin-1) induces NFAT activation / Activation of RAC1 downstream of NMDARs / regulation of cardiac muscle cell action potential / renal absorption / positive regulation of ryanodine-sensitive calcium-release channel activity / regulation of cell communication by electrical coupling involved in cardiac conduction / Synthesis of IP3 and IP4 in the cytosol / negative regulation of peptidyl-threonine phosphorylation / Negative regulation of NMDA receptor-mediated neuronal transmission / Phase 0 - rapid depolarisation / Unblocking of NMDA receptors, glutamate binding and activation / negative regulation of ryanodine-sensitive calcium-release channel activity / protein phosphatase activator activity / RHO GTPases activate PAKs / Ion transport by P-type ATPases / : / inner ear development / Uptake and function of anthrax toxins / Long-term potentiation / Regulation of MECP2 expression and activity / voltage-gated potassium channel activity / Calcineurin activates NFAT / catalytic complex / DARPP-32 events / detection of calcium ion / regulation of cardiac muscle contraction / Smooth Muscle Contraction / regulation of ryanodine-sensitive calcium-release channel activity / RHO GTPases activate IQGAPs / regulation of cardiac muscle contraction by regulation of the release of sequestered calcium ion / calcium channel inhibitor activity / cellular response to interferon-beta / eNOS activation / Protein methylation / voltage-gated potassium channel complex / Activation of AMPK downstream of NMDARs / regulation of release of sequestered calcium ion into cytosol by sarcoplasmic reticulum / Tetrahydrobiopterin (BH4) synthesis, recycling, salvage and regulation / Ion homeostasis / : / titin binding / positive regulation of protein autophosphorylation / regulation of calcium-mediated signaling / sperm midpiece / calcium channel complex / phosphatidylinositol-4,5-bisphosphate binding / substantia nigra development / adenylate cyclase activator activity / Ras activation upon Ca2+ influx through NMDA receptor / regulation of heart rate / sarcomere / FCERI mediated Ca+2 mobilization / protein serine/threonine kinase activator activity / FCGR3A-mediated IL10 synthesis / Antigen activates B Cell Receptor (BCR) leading to generation of second messengers / VEGFR2 mediated vascular permeability / regulation of cytokinesis / VEGFR2 mediated cell proliferation / positive regulation of peptidyl-threonine phosphorylation / spindle microtubule / Translocation of SLC2A4 (GLUT4) to the plasma membrane / positive regulation of receptor signaling pathway via JAK-STAT / RAF activation / cytoplasmic vesicle membrane / Transcriptional activation of mitochondrial biogenesis / positive regulation of protein serine/threonine kinase activity / Stimuli-sensing channels / cellular response to type II interferon / spindle pole / response to calcium ion / RAS processing / Signaling by RAF1 mutants / Signaling by moderate kinase activity BRAF mutants / Paradoxical activation of RAF signaling by kinase inactive BRAF / Signaling downstream of RAS mutants / calcium-dependent protein binding Similarity search - Function | ||||||
Biological species | Xenopus laevis (African clawed frog) Homo sapiens (human) | ||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3.84 Å | ||||||
Authors | Willegems, K. / Kyriakis, E. / Van Petegem, F. / Eldstrom, J. / Fedida, D. | ||||||
Funding support | Canada, 1items
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Citation | Journal: Nat Commun / Year: 2022 Title: Structural and electrophysiological basis for the modulation of KCNQ1 channel currents by ML277. Authors: Katrien Willegems / Jodene Eldstrom / Efthimios Kyriakis / Fariba Ataei / Harutyun Sahakyan / Ying Dou / Sophia Russo / Filip Van Petegem / David Fedida / Abstract: The KCNQ1 ion channel plays critical physiological roles in electrical excitability and K recycling in organs including the heart, brain, and gut. Loss of function is relatively common and can cause ...The KCNQ1 ion channel plays critical physiological roles in electrical excitability and K recycling in organs including the heart, brain, and gut. Loss of function is relatively common and can cause sudden arrhythmic death, sudden infant death, epilepsy and deafness. Here, we report cryogenic electron microscopic (cryo-EM) structures of Xenopus KCNQ1 bound to Ca/Calmodulin, with and without the KCNQ1 channel activator, ML277. A single binding site for ML277 was identified, localized to a pocket lined by the S4-S5 linker, S5 and S6 helices of two separate subunits. Several pocket residues are not conserved in other KCNQ isoforms, explaining specificity. MD simulations and point mutations support this binding location for ML277 in open and closed channels and reveal that prevention of inactivation is an important component of the activator effect. Our work provides direction for therapeutic intervention targeting KCNQ1 loss of function pathologies including long QT interval syndrome and seizures. | ||||||
History |
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-Structure visualization
Structure viewer | Molecule: MolmilJmol/JSmol |
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-Downloads & links
-Download
PDBx/mmCIF format | 7tcp.cif.gz | 342.3 KB | Display | PDBx/mmCIF format |
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PDB format | pdb7tcp.ent.gz | 272.3 KB | Display | PDB format |
PDBx/mmJSON format | 7tcp.json.gz | Tree view | PDBx/mmJSON format | |
Others | Other downloads |
-Validation report
Summary document | 7tcp_validation.pdf.gz | 888.8 KB | Display | wwPDB validaton report |
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Full document | 7tcp_full_validation.pdf.gz | 897.9 KB | Display | |
Data in XML | 7tcp_validation.xml.gz | 55.8 KB | Display | |
Data in CIF | 7tcp_validation.cif.gz | 86.1 KB | Display | |
Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/tc/7tcp ftp://data.pdbj.org/pub/pdb/validation_reports/tc/7tcp | HTTPS FTP |
-Related structure data
Related structure data | 25816MC 7tciC M: map data used to model this data C: citing same article (ref.) |
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Similar structure data | Similarity search - Function & homologyF&H Search |
-Links
-Assembly
Deposited unit |
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1 |
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-Components
#1: Protein | Mass: 62663.398 Da / Num. of mol.: 4 / Fragment: UNP residues 67-610 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Xenopus laevis (African clawed frog) / Gene: kcnq1, kvlqt1 / Cell line (production host): HEK293 / Production host: Homo sapiens (human) / References: UniProt: P70057 #2: Protein | Mass: 16852.545 Da / Num. of mol.: 4 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Homo sapiens (human) / Gene: CALM1, CALM, CAM, CAM1 / Cell line (production host): HEK293 / Production host: Homo sapiens (human) / References: UniProt: P0DP23 #3: Chemical | ChemComp-CA / Has ligand of interest | N | |
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-Experimental details
-Experiment
Experiment | Method: ELECTRON MICROSCOPY |
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EM experiment | Aggregation state: PARTICLE / 3D reconstruction method: single particle reconstruction |
-Sample preparation
Component | Name: Potassium voltage-gated channel subfamily KQT member 1 in complex with calmodulin Type: COMPLEX / Entity ID: #1-#2 / Source: MULTIPLE SOURCES | |||||||||||||||||||||||||||||||||||
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Molecular weight | Value: 0.31756 MDa / Experimental value: NO | |||||||||||||||||||||||||||||||||||
Source (natural) | Organism: Xenopus laevis (African clawed frog) | |||||||||||||||||||||||||||||||||||
Source (recombinant) | Organism: Homo sapiens (human) / Cell: HEK293 | |||||||||||||||||||||||||||||||||||
Buffer solution | pH: 7.2 | |||||||||||||||||||||||||||||||||||
Buffer component |
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Specimen | Conc.: 2 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES | |||||||||||||||||||||||||||||||||||
Specimen support | Grid material: COPPER / Grid mesh size: 400 divisions/in. / Grid type: Quantifoil R1.2/1.3 | |||||||||||||||||||||||||||||||||||
Vitrification | Instrument: FEI VITROBOT MARK IV / Cryogen name: ETHANE / Humidity: 98 % / Chamber temperature: 277.15 K |
-Electron microscopy imaging
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
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Microscopy | Model: FEI TITAN KRIOS |
Electron gun | Electron source: FIELD EMISSION GUN / Accelerating voltage: 300 kV / Illumination mode: FLOOD BEAM |
Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 4900 nm / Nominal defocus min: 360 nm |
Specimen holder | Cryogen: NITROGEN / Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER |
Image recording | Electron dose: 50 e/Å2 / Detector mode: COUNTING / Film or detector model: FEI FALCON IV (4k x 4k) / Num. of grids imaged: 1 / Num. of real images: 19997 |
-Processing
Software | Name: PHENIX / Version: 1.19.2_4158: / Classification: refinement | ||||||||||||||||||||||||
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EM software |
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CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||
Particle selection | Num. of particles selected: 1830000 | ||||||||||||||||||||||||
Symmetry | Point symmetry: C4 (4 fold cyclic) | ||||||||||||||||||||||||
3D reconstruction | Resolution: 3.84 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 71241 / Symmetry type: POINT | ||||||||||||||||||||||||
Refine LS restraints |
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