+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-7296 | |||||||||
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Title | cASIC+mambalgin1 with transmembrane domian | |||||||||
Map data | ||||||||||
Sample |
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Biological species | Gallus gallus (chicken) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 5.7 Å | |||||||||
Authors | Sun D / Yu Y / Xue X | |||||||||
Citation | Journal: Cell Discov / Year: 2018 Title: Cryo-EM structure of the ASIC1a-mambalgin-1 complex reveals that the peptide toxin mambalgin-1 inhibits acid-sensing ion channels through an unusual allosteric effect. Authors: Demeng Sun / You Yu / Xiaobin Xue / Man Pan / Ming Wen / Siyu Li / Qian Qu / Xiaorun Li / Longhua Zhang / Xueming Li / Lei Liu / Maojun Yang / Changlin Tian / Abstract: Acid-sensing ion channels (ASICs) are neuronal voltage-independent Na channels that are activated by extracellular acidification. ASICs play essential roles in a wide range of physiological ...Acid-sensing ion channels (ASICs) are neuronal voltage-independent Na channels that are activated by extracellular acidification. ASICs play essential roles in a wide range of physiological processes, including sodium homeostasis, synaptic plasticity, neurodegeneration, and sensory transduction. Mambalgins, a family of three-finger toxins isolated from black mamba venom, specifically inhibit ASICs to exert strong analgesic effects in vivo, thus are thought to have potential therapeutic values against pain. However, the interaction and inhibition mechanism of mambalgin on ASICs remains elusive. Here, we report a cryo-electron microscopy (cryo-EM) structure of chicken ASIC1a (cASIC1a) in complex with mambalgin-1 toxin at 5.4 Å resolution. Our structure provides the first experimental evidence that mambalgin-1 interacts directly with the extracellular thumb domain of cASIC1a, rather than inserting into the acid-sensing pocket, as previously reported. Binding of mambalgin-1 leads to relocation of the thumb domain that could disrupt the acidic pocket of cASIC1a, illustrating an unusual inhibition mechanism of toxins on ASIC channels through an allosteric effect. These findings establish a structural basis for the toxicity of the mambalgins, and provide crucial insights for the development of new optimized inhibitors of ASICs. | |||||||||
History |
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-Structure visualization
Movie |
Movie viewer |
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Structure viewer | EM map: SurfViewMolmilJmol/JSmol |
Supplemental images |
-Downloads & links
-EMDB archive
Map data | emd_7296.map.gz | 1.8 MB | EMDB map data format | |
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Header (meta data) | emd-7296-v30.xml emd-7296.xml | 7.4 KB 7.4 KB | Display Display | EMDB header |
Images | emd_7296.png | 40.3 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-7296 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-7296 | HTTPS FTP |
-Validation report
Summary document | emd_7296_validation.pdf.gz | 78.6 KB | Display | EMDB validaton report |
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Full document | emd_7296_full_validation.pdf.gz | 77.7 KB | Display | |
Data in XML | emd_7296_validation.xml.gz | 493 B | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-7296 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-7296 | HTTPS FTP |
-Related structure data
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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-Map
File | Download / File: emd_7296.map.gz / Format: CCP4 / Size: 2 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 2.64 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
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-Supplemental data
-Sample components
-Entire : cASIC mambalgin-1
Entire | Name: cASIC mambalgin-1 |
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Components |
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-Supramolecule #1: cASIC mambalgin-1
Supramolecule | Name: cASIC mambalgin-1 / type: complex / ID: 1 / Parent: 0 |
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Source (natural) | Organism: Gallus gallus (chicken) |
Recombinant expression | Organism: Trichoplusia ni (cabbage looper) |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Buffer | pH: 7.5 |
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Vitrification | Cryogen name: ETHANE |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Image recording | Film or detector model: GATAN K2 QUANTUM (4k x 4k) / Average electron dose: 55.0 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
-Image processing
Final reconstruction | Resolution.type: BY AUTHOR / Resolution: 5.7 Å / Resolution method: FSC 0.143 CUT-OFF / Number images used: 103000 |
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Initial angle assignment | Type: RANDOM ASSIGNMENT |
Final angle assignment | Type: RANDOM ASSIGNMENT |