Biological Assembly 1  

Global Symmetry: Cyclic - C3  (3D View)
Global Stoichiometry: Homo 3-mer - A3 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 181.57 kDa 
• Atom Count: 10,242 
• Modelled Residue Count: 1,338 
• Deposited Residue Count: 1,581 
• Unique protein chains: 1

 6VTL

Structure of an acid-sensing ion channel solubilized by styrene maleic acid and in a resting state at high pH

• PDB DOI:  https://doi.org/10.2210/pdb6VTL/pdb
• EM Map EMD-21381: EMDB EMDataResource

• Classification: TRANSPORT PROTEIN
• Organism(s): Gallus gallus
• Expression System: Homo sapiens
• Mutation(s): No 
• Membrane Protein: Yes  OPMPDBTMMemProtMDmpstruc


• Deposited: 2020-02-12 Released: 2020-03-11 
• Deposition Author(s): Yoder, N., Gouaux, E.
• Funding Organization(s): National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK), National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.65 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

The His-Gly motif of acid-sensing ion channels resides in a reentrant 'loop' implicated in gating and ion selectivity.

Yoder, N., Gouaux, E.

(2020) Elife 9

• PubMed: 32496192 
• DOI: https://doi.org/10.7554/eLife.56527
• Primary Citation of Related Structures:  
  6VTK, 6VTL


• PubMed Abstract: 
  

Acid-sensing ion channels (ASICs) are proton-gated members of the epithelial sodium channel/degenerin (ENaC/DEG) superfamily of ion channels and are expressed throughout the central and peripheral nervous systems. The homotrimeric splice variant ASIC1a has been implicated in nociception, fear memory, mood disorders and ischemia. Here, we extract full-length chicken ASIC1 (cASIC1) from cell membranes using styrene maleic acid (SMA) copolymer, elucidating structures of ASIC1 channels in both high pH resting and low pH desensitized conformations by single-particle cryo-electron microscopy (cryo-EM). The structures of resting and desensitized channels reveal a reentrant loop at the amino terminus of ASIC1 that includes the highly conserved 'His-Gly' (HG) motif. The reentrant loop lines the lower ion permeation pathway and buttresses the 'Gly-Ala-Ser' (GAS) constriction, thus providing a structural explanation for the role of the His-Gly dipeptide in the structure and function of ASICs.

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Related Citations: 

• Conserved His-Gly motif of acid-sensing ion channels resides in a reentrant loop implicated in gating and ion selectivity
  Yoder, N., Gouaux, E.
  (2020) Biorxiv --: --

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Organizational Affiliation: 

Howard Hughes Medical Institute, Oregon Health & Science University, Portland, United States.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Acid-sensing ion channel 1	A, B [auth C], C [auth B]	527	Gallus gallus	Mutation(s): 0  Gene Names: ASIC1, ACCN2 Membrane Entity: Yes
UniProt
Find proteins for Q1XA76 (Gallus gallus) Explore Q1XA76  Go to UniProtKB:  Q1XA76

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAG	D [auth A], E [auth A], F [auth C], G [auth C], H [auth B], I [auth B]	2-acetamido-2-deoxy-beta-D-glucopyranose C8 H15 N O6 OVRNDRQMDRJTHS-FMDGEEDCSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.65 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

EM Software:

Task	Software Package	Version
RECONSTRUCTION	cryoSPARC	2
MODEL REFINEMENT	PHENIX	1.14

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2020-03-11 
Deposition Author(s): Yoder, N., Gouaux, E.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Disease (NIH/NIDDK)	United States	5T32DK007680
National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)	United States	5R01NS038631
National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)	United States	5F31NS096782

Revision History  

• Version 1.0: 2020-03-11
  Type: Initial release
  
• Version 1.1: 2020-06-24
  Changes: Database references
• Version 1.2: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Data collection, Derived calculations, Structure summary