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

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
Research Article
  • Cited 57
  • Views 3,554
  • Annotations
Cite this article as: eLife 2017;6:e31054 doi: 10.7554/eLife.31054

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.

Reviewing Editor

  1. Kenton J Swartz, National Institutes of Health, United States

Publication history

  1. Received: August 5, 2017
  2. Accepted: October 11, 2017
  3. Accepted Manuscript published: October 16, 2017 (version 1)
  4. Accepted Manuscript updated: October 18, 2017 (version 2)
  5. Version of Record published: October 24, 2017 (version 3)

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

  • 3,554
    Page views
  • 689
    Downloads
  • 57
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

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)

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

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

  1. Further reading

Further reading

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Zdravka Daneva et al.
    Research Article Updated

    Pannexin 1 (Panx1), an ATP-efflux pathway, has been linked with inflammation in pulmonary capillaries. However, the physiological roles of endothelial Panx1 in the pulmonary vasculature are unknown. Endothelial transient receptor potential vanilloid 4 (TRPV4) channels lower pulmonary artery (PA) contractility and exogenous ATP activates endothelial TRPV4 channels. We hypothesized that endothelial Panx1–ATP–TRPV4 channel signaling promotes vasodilation and lowers pulmonary arterial pressure (PAP). Endothelial, but not smooth muscle, knockout of Panx1 increased PA contractility and raised PAP in mice. Flow/shear stress increased ATP efflux through endothelial Panx1 in PAs. Panx1-effluxed extracellular ATP signaled through purinergic P2Y2 receptor (P2Y2R) to activate protein kinase Cα (PKCα), which in turn activated endothelial TRPV4 channels. Finally, caveolin-1 provided a signaling scaffold for endothelial Panx1, P2Y2R, PKCα, and TRPV4 channels in PAs, promoting their spatial proximity and enabling signaling interactions. These results indicate that endothelial Panx1–P2Y2R–TRPV4 channel signaling, facilitated by caveolin-1, reduces PA contractility and lowers PAP in mice.

    1. Biochemistry and Chemical Biology
    2. Neuroscience
    Lloyd Davis et al.
    Tools and Resources Updated

    Synthetic strategies for optically controlling gene expression may enable the precise spatiotemporal control of genes in any combination of cells that cannot be targeted with specific promoters. We develop an improved genetic code expansion system in Caenorhabditis elegans and use it to create a photoactivatable Cre recombinase. We laser-activate Cre in single neurons within a bilaterally symmetric pair to selectively switch on expression of a loxP-controlled optogenetic channel in the targeted neuron. We use the system to dissect, in freely moving animals, the individual contributions of the mechanosensory neurons PLML/PLMR to the C. elegans touch response circuit, revealing distinct and synergistic roles for these neurons. We thus demonstrate how genetic code expansion and optical targeting can be combined to break the symmetry of neuron pairs and dissect behavioural outputs of individual neurons that cannot be genetically targeted.