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Yorodumi- PDB-6v1y: Cryo-EM Structure of the Hyperpolarization-Activated Potassium Ch... -
+Open data
-Basic information
Entry | Database: PDB / ID: 6v1y | |||||||||
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Title | Cryo-EM Structure of the Hyperpolarization-Activated Potassium Channel KAT1: Octamer | |||||||||
Components | Potassium channel KAT1 | |||||||||
Keywords | TRANSPORT PROTEIN / membrane protein / voltage-gated ion channel / potassium channel | |||||||||
Function / homology | Function and homology information inward rectifier potassium channel activity / monoatomic ion channel complex / identical protein binding / plasma membrane Similarity search - Function | |||||||||
Biological species | Arabidopsis thaliana (thale cress) | |||||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3.8 Å | |||||||||
Authors | Clark, M.D. / Contreras, G.F. / Shen, R. / Perozo, E. | |||||||||
Funding support | United States, 2items
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Citation | Journal: Nature / Year: 2020 Title: Electromechanical coupling in the hyperpolarization-activated K channel KAT1. Authors: Michael David Clark / Gustavo F Contreras / Rong Shen / Eduardo Perozo / Abstract: Voltage-gated potassium (K) channels coordinate electrical signalling and control cell volume by gating in response to membrane depolarization or hyperpolarization. However, although voltage-sensing ...Voltage-gated potassium (K) channels coordinate electrical signalling and control cell volume by gating in response to membrane depolarization or hyperpolarization. However, although voltage-sensing domains transduce transmembrane electric field changes by a common mechanism involving the outward or inward translocation of gating charges, the general determinants of channel gating polarity remain poorly understood. Here we suggest a molecular mechanism for electromechanical coupling and gating polarity in non-domain-swapped K channels on the basis of the cryo-electron microscopy structure of KAT1, the hyperpolarization-activated K channel from Arabidopsis thaliana. KAT1 displays a depolarized voltage sensor, which interacts with a closed pore domain directly via two interfaces and indirectly via an intercalated phospholipid. Functional evaluation of KAT1 structure-guided mutants at the sensor-pore interfaces suggests a mechanism in which direct interaction between the sensor and the C-linker hairpin in the adjacent pore subunit is the primary determinant of gating polarity. We suggest that an inward motion of the S4 sensor helix of approximately 5-7 Å can underlie a direct-coupling mechanism, driving a conformational reorientation of the C-linker and ultimately opening the activation gate formed by the S6 intracellular bundle. This direct-coupling mechanism contrasts with allosteric mechanisms proposed for hyperpolarization-activated cyclic nucleotide-gated channels, and may represent an unexpected link between depolarization- and hyperpolarization-activated channels. | |||||||||
History |
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-Structure visualization
Movie |
Movie viewer |
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Structure viewer | Molecule: MolmilJmol/JSmol |
-Downloads & links
-Download
PDBx/mmCIF format | 6v1y.cif.gz | 611.1 KB | Display | PDBx/mmCIF format |
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PDB format | pdb6v1y.ent.gz | 496.5 KB | Display | PDB format |
PDBx/mmJSON format | 6v1y.json.gz | Tree view | PDBx/mmJSON format | |
Others | Other downloads |
-Validation report
Summary document | 6v1y_validation.pdf.gz | 1.4 MB | Display | wwPDB validaton report |
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Full document | 6v1y_full_validation.pdf.gz | 1.4 MB | Display | |
Data in XML | 6v1y_validation.xml.gz | 105.6 KB | Display | |
Data in CIF | 6v1y_validation.cif.gz | 151.4 KB | Display | |
Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/v1/6v1y ftp://data.pdbj.org/pub/pdb/validation_reports/v1/6v1y | HTTPS FTP |
-Related structure data
Related structure data | 21019MC 6v1xC M: map data used to model this data C: citing same article (ref.) |
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Similar structure data | |
EM raw data | EMPIAR-11054 (Title: Cryo-EM Structure of the Hyperpolarization-Activated Potassium Channel KAT1 Data size: 3.1 TB Data #1: unaligned non-gain-ref movies [micrographs - multiframe]) |
-Links
-Assembly
Deposited unit |
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-Components
#1: Protein | Mass: 59639.594 Da / Num. of mol.: 8 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Arabidopsis thaliana (thale cress) / Gene: KAT1, At5g46240, MPL12.2 / Production host: Spodoptera frugiperda (fall armyworm) / References: UniProt: Q39128 #2: Chemical | ChemComp-QNP / ( #3: Chemical | ChemComp-QNJ / ( 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: Hyperpolarization-Activated Potassium Channel KAT1 / Type: COMPLEX / Entity ID: #1 / Source: RECOMBINANT | |||||||||||||||||||||||||
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Molecular weight | Experimental value: NO | |||||||||||||||||||||||||
Source (natural) | Organism: Arabidopsis thaliana (thale cress) | |||||||||||||||||||||||||
Source (recombinant) | Organism: Spodoptera frugiperda (fall armyworm) | |||||||||||||||||||||||||
Buffer solution | pH: 7.4 | |||||||||||||||||||||||||
Buffer component |
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Specimen | Conc.: 5 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES | |||||||||||||||||||||||||
Specimen support | Grid material: COPPER / Grid mesh size: 200 divisions/in. / Grid type: Quantifoil R1.2/1.3 | |||||||||||||||||||||||||
Vitrification | Instrument: FEI VITROBOT MARK IV / Cryogen name: ETHANE / Humidity: 100 % / Chamber temperature: 295 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 magnification: 130000 X / Nominal defocus max: 2500 nm / Nominal defocus min: 1000 nm / Cs: 2.7 mm |
Specimen holder | Cryogen: NITROGEN / Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER |
Image recording | Average exposure time: 12 sec. / Electron dose: 50 e/Å2 / Detector mode: SUPER-RESOLUTION / Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Num. of grids imaged: 1 / Num. of real images: 1502 |
EM imaging optics | Energyfilter slit width: 20 eV |
Image scans | Movie frames/image: 40 / Used frames/image: 1-40 |
-Processing
EM software |
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CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||||||||||||||||||
Symmetry | Point symmetry: C4 (4 fold cyclic) | ||||||||||||||||||||||||||||||||||||||||
3D reconstruction | Resolution: 3.8 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 91689 / Symmetry type: POINT | ||||||||||||||||||||||||||||||||||||||||
Atomic model building | Space: REAL |