6CDU

Crystal structure of a chimeric human alpha1GABAA receptor in complex with alphaxalone


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.45 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.227 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structural basis of neurosteroid anesthetic action on GABAAreceptors.

Chen, Q.Wells, M.M.Arjunan, P.Tillman, T.S.Cohen, A.E.Xu, Y.Tang, P.

(2018) Nat Commun 9: 3972-3972

  • DOI: 10.1038/s41467-018-06361-4
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Type A γ-aminobutyric acid receptors (GABA <sub>A </sub>Rs) are inhibitory pentameric ligand-gated ion channels in the brain. Many anesthetics and neurosteroids act through binding to the GABA <sub>A </sub>R transmembrane domain (TMD), but the struct ...

    Type A γ-aminobutyric acid receptors (GABA A Rs) are inhibitory pentameric ligand-gated ion channels in the brain. Many anesthetics and neurosteroids act through binding to the GABA A R transmembrane domain (TMD), but the structural basis of their actions is not well understood and no resting-state GABA A R structure has been determined. Here, we report crystal structures of apo and the neurosteroid anesthetic alphaxalone-bound desensitized chimeric α1GABA A R (ELIC-α1GABA A R). The chimera retains the functional and pharmacological properties of GABA A Rs, including potentiation, activation and desensitization by alphaxalone. The apo-state structure reveals an unconventional activation gate at the intracellular end of the pore. The desensitized structure illustrates molecular determinants for alphaxalone binding to an inter-subunit TMD site. These structures suggest a plausible signaling pathway from alphaxalone binding at the bottom of the TMD to the channel gate in the pore-lining TM2 through the TM1-TM2 linker. The study provides a framework to discover new GABA A R modulators with therapeutic potential.


    Organizational Affiliation

    Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA.,Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, 15260, USA. ptang@pitt.edu.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15260, USA. ptang@pitt.edu.,Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, 15260, USA.,Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA, 15260, USA.,Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, 15260, USA. ptang@pitt.edu.,Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, 15260, USA.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15260, USA.,Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, 15260, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
chimeric alpha1GABAA receptor
A, B, C, D, E, F, G, H, I, J
324Homo sapiensDickeya dadantii (strain 3937)
This entity is chimeric
Mutation(s): 0 
Gene Names: GABRA1,
Find proteins for P14867 (Homo sapiens)
Go to Gene View: GABRA1
Go to UniProtKB:  P14867
Find proteins for E0SJQ4 (Dickeya dadantii (strain 3937))
Go to UniProtKB:  E0SJQ4
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EY4
Query on EY4

Download SDF File 
Download CCD File 
A, B, D, E, F, G, H, I
(3a,5a)-3-Hydroxypregnane-11,20-dione
alphaxalone
C21 H32 O3
DUHUCHOQIDJXAT-OLVMNOGESA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.45 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.227 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 108.202α = 90.00
b = 263.529β = 110.91
c = 109.160γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
Aimlessdata scaling
XDSdata reduction
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Human Genome Research InstituteUnited StatesR01GM056257

Revision History 

  • Version 1.0: 2018-08-22
    Type: Initial release
  • Version 1.1: 2018-10-03
    Type: Data collection, Database references
  • Version 1.2: 2018-10-10
    Type: Data collection, Database references, Structure summary
  • Version 1.3: 2018-10-24
    Type: Data collection, Database references, Structure summary