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Open data
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Basic information
Entry | Database: PDB / ID: 6n26 | |||||||||
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Title | BEST1 calcium-free closed state | |||||||||
![]() | Bestrophin homolog | |||||||||
![]() | MEMBRANE PROTEIN / ion channel / calcium activated chloride channel / eukaryotic membrane protein / anion channel / transport protein / ligand gated ion channel | |||||||||
Function / homology | Bestrophin-1 / Stimuli-sensing channels / Bestrophin / Bestrophin/UPF0187 / Bestrophin, RFP-TM, chloride channel / chloride channel activity / membrane / metal ion binding / Bestrophin 1![]() | |||||||||
Biological species | ![]() ![]() | |||||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3 Å | |||||||||
![]() | Miller, A.N. / Vaisey, G. / Long, S.B. | |||||||||
Funding support | ![]()
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![]() | ![]() Title: Molecular mechanisms of gating in the calcium-activated chloride channel bestrophin. Authors: Alexandria N Miller / George Vaisey / Stephen B Long / ![]() Abstract: Bestrophin (BEST1-4) ligand-gated chloride (Cl) channels are activated by calcium (Ca). Mutation of BEST1 causes retinal disease. Partly because bestrophin channels have no sequence or structural ...Bestrophin (BEST1-4) ligand-gated chloride (Cl) channels are activated by calcium (Ca). Mutation of BEST1 causes retinal disease. Partly because bestrophin channels have no sequence or structural similarity to other ion channels, the molecular mechanisms underlying gating are unknown. Here, we present a series of cryo-electron microscopy structures of chicken BEST1, determined at 3.1 Å resolution or better, that represent the channel's principal gating states. Unlike other channels, opening of the pore is due to the repositioning of tethered pore-lining helices within a surrounding protein shell that dramatically widens a neck of the pore through a concertina of amino acid rearrangements. The neck serves as both the activation and the inactivation gate. Ca binding instigates opening of the neck through allosteric means whereas inactivation peptide binding induces closing. An aperture within the otherwise wide pore controls anion permeability. The studies define a new molecular paradigm for gating among ligand-gated ion channels. | |||||||||
History |
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Structure visualization
Movie |
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Structure viewer | Molecule: ![]() ![]() |
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Downloads & links
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Download
PDBx/mmCIF format | ![]() | 284.3 KB | Display | ![]() |
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PDB format | ![]() | 241.4 KB | Display | ![]() |
PDBx/mmJSON format | ![]() | Tree view | ![]() | |
Others | ![]() |
-Validation report
Arichive directory | ![]() ![]() | HTTPS FTP |
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-Related structure data
Related structure data | ![]() 9324MC ![]() 9321C ![]() 9322C ![]() 9323C ![]() 9325C ![]() 9326C ![]() 6n23C ![]() 6n24C ![]() 6n25C ![]() 6n27C ![]() 6n28C C: citing same article ( M: map data used to model this data |
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Similar structure data |
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Links
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Assembly
Deposited unit | ![]()
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Components
#1: Protein | Mass: 40761.727 Da / Num. of mol.: 5 Source method: isolated from a genetically manipulated source Source: (gene. exp.) ![]() ![]() ![]() |
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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 |
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Sample preparation
Component | Name: BEST1 calcium-free closed state / Type: COMPLEX / Entity ID: all / Source: RECOMBINANT |
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Molecular weight | Experimental value: NO |
Source (natural) | Organism: ![]() ![]() |
Source (recombinant) | Organism: ![]() |
Buffer solution | pH: 7.5 |
Specimen | Conc.: 5 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES |
Specimen support | Details: unspecified |
Vitrification | Instrument: FEI VITROBOT MARK IV / Cryogen name: ETHANE / Humidity: 100 % / Chamber temperature: 293 K |
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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: ![]() |
Electron lens | Mode: BRIGHT FIELD / Alignment procedure: COMA FREE |
Specimen holder | Cryogen: NITROGEN / Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER |
Image recording | Average exposure time: 10 sec. / Electron dose: 76 e/Å2 / Detector mode: SUPER-RESOLUTION / Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Num. of grids imaged: 1 |
Image scans | Movie frames/image: 40 / Used frames/image: 1-40 |
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Processing
EM software |
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CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||||||||||||||||||
Symmetry | Point symmetry: C5 (5 fold cyclic) | ||||||||||||||||||||||||||||||||||||||||
3D reconstruction | Resolution: 3 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 132909 / Algorithm: FOURIER SPACE / Num. of class averages: 1 / Symmetry type: POINT | ||||||||||||||||||||||||||||||||||||||||
Atomic model building | B value: 87 / Protocol: OTHER / Space: REAL | ||||||||||||||||||||||||||||||||||||||||
Atomic model building | PDB-ID: 4RDQ Pdb chain-ID: A / Pdb chain residue range: 2-367 | ||||||||||||||||||||||||||||||||||||||||
Refinement | Highest resolution: 3 Å |