Cryo-EM structure of the benzodiazepine-sensitive α1β1γ2S tri-heteromeric GABAA receptor in complex with GABA

  1. Swastik Phulera
  2. Hongtao Zhu
  3. Jie Yu
  4. Derek P Claxton
  5. Nate Yoder
  6. Craig Yoshioka
  7. Eric Gouaux  Is a corresponding author
  1. Oregon Health and Science University, United States

Abstract

Fast inhibitory neurotransmission in mammalian nervous system is largely mediated by GABAA receptors, chloride-selective members of the superfamily of pentameric Cys-loop receptors. Native GABAA receptors are heteromeric assemblies sensitive to many important drugs, from sedatives to anesthetics and anticonvulsant agents, with mutant forms of GABAA receptors implicated in multiple neurological diseases. Despite profound importance of heteromeric GABAA receptors in neuroscience and medicine, they have proven recalcitrant to structure determination. Here we present the structure of tri-heteromeric α1β1γ2SEM GABAA receptor in complex with GABA, determined by single particle cryo-EM at 3.1-3.8 Å resolution, elucidating molecular principles of receptor assembly and agonist binding. Remarkable N-linked glycosylation on the α1 subunit occludes the extracellular vestibule of the ion channel and is poised to modulate receptor assembly and perhaps ion channel gating. Our work provides a pathway to structural studies of heteromeric GABAA receptors and a framework for rational design of novel therapeutic agents.

Data availability

EM density maps have been deposited to EMDB, the structure of the triheteromeric receptor has been deposited to the PDB

The following data sets were generated

Article and author information

Author details

  1. Swastik Phulera

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Hongtao Zhu

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jie Yu

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Derek P Claxton

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Nate Yoder

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Craig Yoshioka

    Vollum Institute, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Eric Gouaux

    Vollum Institute, Oregon Health and Science University, Portland, United States
    For correspondence
    gouauxe@ohsu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8549-2360

Funding

National Institute of General Medical Sciences (R01 GM100400)

  • Eric Gouaux

Howard Hughes Medical Institute

  • Eric Gouaux

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2018, Phulera et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Swastik Phulera
  2. Hongtao Zhu
  3. Jie Yu
  4. Derek P Claxton
  5. Nate Yoder
  6. Craig Yoshioka
  7. Eric Gouaux
(2018)
Cryo-EM structure of the benzodiazepine-sensitive α1β1γ2S tri-heteromeric GABAA receptor in complex with GABA
eLife 7:e39383.
https://doi.org/10.7554/eLife.39383

Share this article

https://doi.org/10.7554/eLife.39383

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