1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics

Anti-diabetic drug binding site in a mammalian KATP channel revealed by Cryo-EM

  1. Gregory M Martin
  2. Balamurugan Kandasamy
  3. Frank DiMaio
  4. Craig Yoshioka  Is a corresponding author
  5. Show-Ling Shyng  Is a corresponding author
  1. Oregon Health and Science University, United States
  2. University of Washington, United States
https://doi.org/10.7554/eLife.31054
Share this article
Cite this article
  1. Gregory M Martin
  2. Balamurugan Kandasamy
  3. Frank DiMaio
  4. Craig Yoshioka
  5. Show-Ling Shyng
(2017)
Anti-diabetic drug binding site in a mammalian KATP channel revealed by Cryo-EM
eLife 6:e31054.
https://doi.org/10.7554/eLife.31054
  2. Download BibTeX
  3. Download .RIS

Abstract

Sulfonylureas are anti-diabetic medications that act by inhibiting pancreatic KATP channels composed of SUR1 and Kir6.2. The mechanism by which these drugs interact with and inhibit the channel has been extensively investigated, yet it remains unclear where the drug binding pocket resides. Here, we present a cryo-EM structure of a hamster SUR1/rat Kir6.2 channel bound to a high-affinity sulfonylurea drug glibenclamide and ATP at 3.63Å resolution, which reveals unprecedented details of the ATP and glibenclamide binding sites. Importantly, the structure shows for the first time that glibenclamide is lodged in the transmembrane bundle of the SUR1-ABC core connected to the first nucleotide binding domain near the inner leaflet of the lipid bilayer. Mutation of residues predicted to interact with glibenclamide in our model led to reduced sensitivity to glibenclamide. Our structure provides novel mechanistic insights of how sulfonylureas and ATP interact with the KATP channel complex to inhibit channel activity.

Data availability

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Gregory M Martin

    Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Balamurugan Kandasamy

    Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Frank DiMaio

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7524-8938

  4. Craig Yoshioka

    Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States
    For correspondence
    yoshiokc@ohsu.edu
    Competing interests
    The authors declare that no competing interests exist.

  5. Show-Ling Shyng

    Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, United States
    For correspondence
    shyngs@ohsu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8230-8820

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (R01DK066485)

  • Show-Ling Shyng

National Institute of Diabetes and Digestive and Kidney Diseases (F31DK105800)

  • Gregory M Martin

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

Copyright

© 2017, Martin 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.

Metrics

  • 4,785
    views
  • 826
    downloads
  • 127
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Gregory M Martin
  2. Balamurugan Kandasamy
  3. Frank DiMaio
  4. Craig Yoshioka
  5. Show-Ling Shyng
(2017)
Anti-diabetic drug binding site in a mammalian KATP channel revealed by Cryo-EM
eLife 6:e31054.
https://doi.org/10.7554/eLife.31054

Share this article

https://doi.org/10.7554/eLife.31054

Categories and tags

Research organism

Further reading

    1. Structural Biology and Molecular Biophysics
    2. Neuroscience

    Molecular structure of human KATP in complex with ATP and ADP

    Kenneth Pak Kin Lee, Jue Chen, Roderick MacKinnon
    Research Article Updated

    In many excitable cells, KATP channels respond to intracellular adenosine nucleotides: ATP inhibits while ADP activates. We present two structures of the human pancreatic KATP channel, containing the ABC transporter SUR1 and the inward-rectifier K+ channel Kir6.2, in the presence of Mg2+ and nucleotides. These structures, referred to as quatrefoil and propeller forms, were determined by single-particle cryo-EM at 3.9 Å and 5.6 Å, respectively. In both forms, ATP occupies the inhibitory site in Kir6.2. The nucleotide-binding domains of SUR1 are dimerized with Mg2+-ATP in the degenerate site and Mg2+-ADP in the consensus site. A lasso extension forms an interface between SUR1 and Kir6.2 adjacent to the ATP site in the propeller form and is disrupted in the quatrefoil form. These structures support the role of SUR1 as an ADP sensor and highlight the lasso extension as a key regulatory element in ADP’s ability to override ATP inhibition.

    1. Biochemistry and Chemical Biology
    2. Microbiology and Infectious Disease

    On the role of VP3-PI3P interaction in birnavirus endosomal membrane targeting

    Flavia A Zanetti, Ignacio Fernandez ... Laura Ruth Delgui
    Research Article

    Birnaviruses are a group of double-stranded RNA (dsRNA) viruses infecting birds, fish, and insects. Early endosomes (EE) constitute the platform for viral replication. Here, we study the mechanism of birnaviral targeting of EE membranes. Using the Infectious Bursal Disease Virus (IBDV) as a model, we validate that the viral protein 3 (VP3) binds to phosphatidylinositol-3-phosphate (PI3P) present in EE membranes. We identify the domain of VP3 involved in PI3P-binding, named P2 and localized in the core of VP3, and establish the critical role of the arginine at position 200 (R200), conserved among all known birnaviruses. Mutating R200 abolishes viral replication. Moreover, we propose a two-stage modular mechanism for VP3 association with EE. Firstly, the carboxy-terminal region of VP3 adsorbs on the membrane, and then the VP3 core reinforces the membrane engagement by specifically binding PI3P through its P2 domain, additionally promoting PI3P accumulation.

    1. Biochemistry and Chemical Biology
    2. Microbiology and Infectious Disease

    Cellular Energy Production: Mycofactocin and the mycobacterial electron transport chain

    Stephanie M Stuteley, Ghader Bashiri
    Insight

    In the bacterium M. smegmatis, an enzyme called MftG allows the cofactor mycofactocin to transfer electrons released during ethanol metabolism to the electron transport chain.