+Open data
-Basic information
Entry | Database: PDB / ID: 8vta | ||||||
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Title | SthK R120A in the presence of PIP2 and cAMP | ||||||
Components | Transcriptional regulator, Crp/Fnr family | ||||||
Keywords | TRANSPORT PROTEIN / cyclic-nucleotide binding / potassium channel / lipid modulation | ||||||
Function / homology | Function and homology information monoatomic ion transmembrane transport / protein-containing complex binding / membrane Similarity search - Function | ||||||
Biological species | Spirochaeta thermophila (bacteria) | ||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3 Å | ||||||
Authors | Schmidpeter, P.A.M. / Thon, O. / Nimigean, C.M. | ||||||
Funding support | United States, 1items
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Citation | Journal: Nat Commun / Year: 2024 Title: PIP2 inhibits pore opening of the cyclic nucleotide-gated channel SthK. Authors: Oliver Thon / Zhihan Wang / Philipp A M Schmidpeter / Crina M Nimigean / Abstract: The signaling lipid phosphatidylinositol-4,5-bisphosphate (PIP2) regulates many ion channels. It inhibits eukaryotic cyclic nucleotide-gated (CNG) channels while activating their relatives, the ...The signaling lipid phosphatidylinositol-4,5-bisphosphate (PIP2) regulates many ion channels. It inhibits eukaryotic cyclic nucleotide-gated (CNG) channels while activating their relatives, the hyperpolarization-activated and cyclic nucleotide-modulated (HCN) channels. The prokaryotic SthK channel from Spirochaeta thermophila shares features with CNG and HCN channels and is an established model for this channel family. Here, we show SthK activity is inhibited by PIP2. A cryo-EM structure of SthK in nanodiscs reveals a PIP2-fitting density coordinated by arginine and lysine residues from the S4 helix and the C-linker, located between voltage-sensing and pore domains of adjacent subunits. Mutation of two arginine residues weakens PIP2 inhibition with the double mutant displaying insensitivity to PIP2. We propose that PIP2 inhibits SthK by gluing S4 and S6 together, stabilizing a resting channel conformation. The PIP2 binding site is partially conserved in CNG channels suggesting the possibility of a similar inhibition mechanism in the eukaryotic homologs. | ||||||
History |
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-Structure visualization
Structure viewer | Molecule: MolmilJmol/JSmol |
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-Downloads & links
-Download
PDBx/mmCIF format | 8vta.cif.gz | 349.7 KB | Display | PDBx/mmCIF format |
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PDB format | pdb8vta.ent.gz | 280.8 KB | Display | PDB format |
PDBx/mmJSON format | 8vta.json.gz | Tree view | PDBx/mmJSON format | |
Others | Other downloads |
-Validation report
Summary document | 8vta_validation.pdf.gz | 2.2 MB | Display | wwPDB validaton report |
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Full document | 8vta_full_validation.pdf.gz | 2.2 MB | Display | |
Data in XML | 8vta_validation.xml.gz | 63.7 KB | Display | |
Data in CIF | 8vta_validation.cif.gz | 89.6 KB | Display | |
Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/vt/8vta ftp://data.pdbj.org/pub/pdb/validation_reports/vt/8vta | HTTPS FTP |
-Related structure data
Related structure data | 43521MC 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: 50675.031 Da / Num. of mol.: 4 / Mutation: R120A Source method: isolated from a genetically manipulated source Source: (gene. exp.) Spirochaeta thermophila (bacteria) / Gene: Spith_0644 / Production host: Escherichia coli BL21(DE3) (bacteria) / Variant (production host): C41 / References: UniProt: G0GA88 #2: Chemical | ChemComp-CMP / #3: Chemical | ChemComp-PT5 / [( #4: Chemical | ChemComp-PCW / Has ligand of interest | Y | |
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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: tetrameric SthK protein / Type: COMPLEX Details: SthK R120A in complex with cAMP reconstituted into MSP1E3 nanodiscs containing PIP2 Entity ID: #1 / Source: RECOMBINANT | ||||||||||||||||||||
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Molecular weight | Value: 0.2 MDa / Experimental value: NO | ||||||||||||||||||||
Source (natural) | Organism: Spirochaeta thermophila (bacteria) | ||||||||||||||||||||
Source (recombinant) | Organism: Escherichia coli (E. coli) / Strain: C41 (DE3) | ||||||||||||||||||||
Buffer solution | pH: 7.4 | ||||||||||||||||||||
Buffer component |
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Specimen | Conc.: 7.5 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES Details: nanodisc reconstitution was carried out in the presence of DOPC, POPG, and PIP2 | ||||||||||||||||||||
Specimen support | Grid material: GOLD / Grid mesh size: 300 divisions/in. / Grid type: UltrAuFoil R1.2/1.3 | ||||||||||||||||||||
Vitrification | Instrument: FEI VITROBOT MARK IV / Cryogen name: ETHANE / Humidity: 100 % / Chamber temperature: 298 K / Details: 30 s incubation 2 s blotting blot force -4 |
-Electron microscopy imaging
Experimental equipment | Model: Talos Arctica / Image courtesy: FEI Company |
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Microscopy | Model: FEI TALOS ARCTICA |
Electron gun | Electron source: FIELD EMISSION GUN / Accelerating voltage: 200 kV / Illumination mode: FLOOD BEAM |
Electron lens | Mode: BRIGHT FIELD / Nominal magnification: 36000 X / Nominal defocus max: 2900 nm / Nominal defocus min: 900 nm |
Specimen holder | Cryogen: NITROGEN |
Image recording | Electron dose: 51.03 e/Å2 / Film or detector model: GATAN K3 (6k x 4k) |
-Processing
EM software |
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CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||||||||||||||
Particle selection | Num. of particles selected: 781418 | ||||||||||||||||||||||||||||||||||||
Symmetry | Point symmetry: C4 (4 fold cyclic) | ||||||||||||||||||||||||||||||||||||
3D reconstruction | Resolution: 3 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 228035 / Symmetry type: POINT | ||||||||||||||||||||||||||||||||||||
Atomic model building | Protocol: FLEXIBLE FIT / Space: REAL | ||||||||||||||||||||||||||||||||||||
Atomic model building | PDB-ID: 6CJQ Accession code: 6CJQ / Source name: PDB / Type: experimental model |