+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-25816 | |||||||||
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Title | Structure of Xenopus KCNQ1-CaM | |||||||||
Map data | ||||||||||
Sample |
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Keywords | ion channel / TRANSPORT PROTEIN | |||||||||
Function / homology | Function and homology information regulation of gastric acid secretion / membrane repolarization / delayed rectifier potassium channel activity / outward rectifier potassium channel activity / CaM pathway / Cam-PDE 1 activation / intestinal absorption / 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 / CaM pathway / Cam-PDE 1 activation / intestinal absorption / Sodium/Calcium exchangers / Calmodulin induced events / Reduction of cytosolic Ca++ levels / Activation of Ca-permeable Kainate Receptor / CREB1 phosphorylation through the activation of CaMKII/CaMKK/CaMKIV cascasde / 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) / negative regulation of calcium ion export across plasma membrane / organelle localization by membrane tethering / Activation of RAC1 downstream of NMDARs / regulation of cardiac muscle cell action potential / mitochondrion-endoplasmic reticulum membrane tethering / CLEC7A (Dectin-1) induces NFAT activation / autophagosome membrane docking / renal absorption / positive regulation of ryanodine-sensitive calcium-release channel activity / Negative regulation of NMDA receptor-mediated neuronal transmission / regulation of cell communication by electrical coupling involved in cardiac conduction / Unblocking of NMDA receptors, glutamate binding and activation / negative regulation of peptidyl-threonine phosphorylation / Synthesis of IP3 and IP4 in the cytosol / Phase 0 - rapid depolarisation / protein phosphatase activator activity / RHO GTPases activate PAKs / voltage-gated potassium channel activity / inner ear development / positive regulation of cyclic-nucleotide phosphodiesterase activity / positive regulation of phosphoprotein phosphatase activity / Long-term potentiation / Ion transport by P-type ATPases / Uptake and function of anthrax toxins / Calcineurin activates NFAT / Regulation of MECP2 expression and activity / catalytic complex / DARPP-32 events / detection of calcium ion / negative regulation of ryanodine-sensitive calcium-release channel activity / Smooth Muscle Contraction / RHO GTPases activate IQGAPs / regulation of cardiac muscle contraction / calcium channel inhibitor activity / cellular response to interferon-beta / regulation of cardiac muscle contraction by regulation of the release of sequestered calcium ion / Protein methylation / voltage-gated potassium channel complex / Activation of AMPK downstream of NMDARs / eNOS activation / regulation of release of sequestered calcium ion into cytosol by sarcoplasmic reticulum / regulation of calcium-mediated signaling / positive regulation of protein dephosphorylation / titin binding / regulation of ryanodine-sensitive calcium-release channel activity / Tetrahydrobiopterin (BH4) synthesis, recycling, salvage and regulation / Ion homeostasis / positive regulation of protein autophosphorylation / sperm midpiece / phosphatidylinositol-4,5-bisphosphate binding / calcium channel complex / substantia nigra development / adenylate cyclase activator activity / Ras activation upon Ca2+ influx through NMDA receptor / regulation of heart rate / protein serine/threonine kinase activator activity / sarcomere / FCERI mediated Ca+2 mobilization / FCGR3A-mediated IL10 synthesis / VEGFR2 mediated vascular permeability / positive regulation of peptidyl-threonine phosphorylation / Antigen activates B Cell Receptor (BCR) leading to generation of second messengers / VEGFR2 mediated cell proliferation / regulation of cytokinesis / Translocation of SLC2A4 (GLUT4) to the plasma membrane / spindle microtubule / RAF activation / positive regulation of receptor signaling pathway via JAK-STAT / cytoplasmic vesicle membrane / positive regulation of protein serine/threonine kinase activity / Transcriptional activation of mitochondrial biogenesis / Stimuli-sensing channels / spindle pole / cellular response to type II interferon / response to calcium ion / RAS processing / calcium-dependent protein binding / Inactivation, recovery and regulation of the phototransduction cascade / Signaling by RAF1 mutants / Signaling by moderate kinase activity BRAF mutants / Paradoxical activation of RAF signaling by kinase inactive BRAF Similarity search - Function | |||||||||
Biological species | Xenopus laevis (African clawed frog) / Homo sapiens (human) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.84 Å | |||||||||
Authors | Willegems K / Kyriakis E | |||||||||
Funding support | Canada, 1 items
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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
Supplemental images |
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-Downloads & links
-EMDB archive
Map data | emd_25816.map.gz | 162.1 MB | EMDB map data format | |
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Header (meta data) | emd-25816-v30.xml emd-25816.xml | 14.7 KB 14.7 KB | Display Display | EMDB header |
FSC (resolution estimation) | emd_25816_fsc.xml | 17.4 KB | Display | FSC data file |
Images | emd_25816.png | 82.1 KB | ||
Filedesc metadata | emd-25816.cif.gz | 6.1 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-25816 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-25816 | HTTPS FTP |
-Related structure data
Related structure data | 7tcpMC 7tciC C: citing same article (ref.) M: atomic model generated by this map |
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Similar structure data | Similarity search - Function & homologyF&H Search |
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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Related items in Molecule of the Month |
-Map
File | Download / File: emd_25816.map.gz / Format: CCP4 / Size: 209.3 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||
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Voxel size | X=Y=Z: 0.73 Å | ||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||
Details | EMDB XML:
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-Supplemental data
-Sample components
-Entire : Potassium voltage-gated channel subfamily KQT member 1 in complex...
Entire | Name: Potassium voltage-gated channel subfamily KQT member 1 in complex with calmodulin |
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Components |
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-Supramolecule #1: Potassium voltage-gated channel subfamily KQT member 1 in complex...
Supramolecule | Name: Potassium voltage-gated channel subfamily KQT member 1 in complex with calmodulin type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1-#2 |
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Source (natural) | Organism: Xenopus laevis (African clawed frog) |
Molecular weight | Theoretical: 317.56 KDa |
-Macromolecule #1: Potassium voltage-gated channel subfamily KQT member 1
Macromolecule | Name: Potassium voltage-gated channel subfamily KQT member 1 type: protein_or_peptide / ID: 1 / Number of copies: 4 / Enantiomer: LEVO |
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Source (natural) | Organism: Xenopus laevis (African clawed frog) |
Molecular weight | Theoretical: 62.663398 KDa |
Recombinant expression | Organism: Homo sapiens (human) |
Sequence | String: MATDPPRPTI NLDPRVSIYS GRRPLLSRTN IQGRVYNFLE RPTGWKCFVY HFTVFLIVLI CLIFSVLSTI QQYNNLATET LFWMEIVLV VFFGAEYVVR LWSAGCRSKY VGVWGRLRFA RKPISVIDLI VVVASVIVLC VGSNGQVFAT SAIRGIRFLQ I LRMLHVDR ...String: MATDPPRPTI NLDPRVSIYS GRRPLLSRTN IQGRVYNFLE RPTGWKCFVY HFTVFLIVLI CLIFSVLSTI QQYNNLATET LFWMEIVLV VFFGAEYVVR LWSAGCRSKY VGVWGRLRFA RKPISVIDLI VVVASVIVLC VGSNGQVFAT SAIRGIRFLQ I LRMLHVDR QGGTWRLLGS VVFIHRQELI TTLYIGFLGL IFSSYFVYLA EKDAIDSSGE YQFGSYADAL WWGVVTVTTI GY GDKVPQT WIGKTIASCF SVFAISFFAL PAGILGSGFA LKVQQKQRQK HFNRQIPAAA SLIQTAWRCY AAENPDSATW KIY IRKQSR NHHLMSPSPK PKKSAMVKKK KIRTERDEGS TDKMLNIPHI TYDHVADDRK NDGYSVESYE NTVRKPFGFL DPST GPFIR TSSFTDDLDM EGDTLLTPIT HISELKEHHR AAIKVIRRMQ YFVAKKKFQQ ARKPYDVRDV IEQYSQGHLN LMVRI KELQ RRLDQSLGKP SLFLSVSDKV KDKGINTIGS RLNRVEDKVT QMDHKLNLIT DMLHHLLTNQ QSNS UniProtKB: Potassium voltage-gated channel subfamily KQT member 1 |
-Macromolecule #2: Calmodulin-1
Macromolecule | Name: Calmodulin-1 / type: protein_or_peptide / ID: 2 / Number of copies: 4 / Enantiomer: LEVO |
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Source (natural) | Organism: Homo sapiens (human) |
Molecular weight | Theoretical: 16.852545 KDa |
Recombinant expression | Organism: Homo sapiens (human) |
Sequence | String: MADQLTEEQI AEFKEAFSLF DKDGDGTITT KELGTVMRSL GQNPTEAELQ DMINEVDADG NGTIDFPEFL TMMARKMKDT DSEEEIREA FRVFDKDGNG YISAAELRHV MTNLGEKLTD EEVDEMIREA DIDGDGQVNY EEFVQMMTAK UniProtKB: Calmodulin-1 |
-Macromolecule #3: CALCIUM ION
Macromolecule | Name: CALCIUM ION / type: ligand / ID: 3 / Number of copies: 12 / Formula: CA |
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Molecular weight | Theoretical: 40.078 Da |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Concentration | 2 mg/mL | |||||||||||||||||||||
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Buffer | pH: 7.2 Component:
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Grid | Model: Quantifoil R1.2/1.3 / Material: COPPER / Mesh: 400 / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Time: 25 sec. | |||||||||||||||||||||
Vitrification | Cryogen name: ETHANE / Chamber humidity: 98 % / Chamber temperature: 277.15 K / Instrument: FEI VITROBOT MARK IV |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELDBright-field microscopy / Nominal defocus max: 4.9 µm / Nominal defocus min: 0.36 µm |
Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
Image recording | Film or detector model: FEI FALCON IV (4k x 4k) / Detector mode: COUNTING / Number grids imaged: 1 / Number real images: 19997 / Average electron dose: 50.0 e/Å2 |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |