1. Structural Biology and Molecular Biophysics

Structural basis of phosphatidylcholine recognition by the C2-domain of cytosolic phospholipase A2α

  1. Yoshinori Hirano
  2. Yong-Guang Gao
  3. Daniel J Stephenson
  4. Ngoc T Vu
  5. Lucy Malinina
  6. Dhirendra K Simanshu
  7. Charles E Chalfant
  8. Dinshaw J Patel
  9. Rhoderick E Brown  Is a corresponding author
  1. Memorial Sloan Kettering Cancer Center, United States
  2. University of Minnesota, United States
  3. University of South Florida, United States
  4. Virginia Commonwealth University, United States
https://doi.org/10.7554/eLife.44760
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Cite this article
  1. Yoshinori Hirano
  2. Yong-Guang Gao
  3. Daniel J Stephenson
  4. Ngoc T Vu
  5. Lucy Malinina
  6. Dhirendra K Simanshu
  7. Charles E Chalfant
  8. Dinshaw J Patel
  9. Rhoderick E Brown
(2019)
Structural basis of phosphatidylcholine recognition by the C2-domain of cytosolic phospholipase A2α
eLife 8:e44760.
https://doi.org/10.7554/eLife.44760
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  3. Download .RIS

Abstract

Ca2+-stimulated translocation of cytosolic phospholipase A2α (cPLA2α) to the Golgi induces arachidonic acid production, the rate-limiting step in pro-inflammatory eicosanoid synthesis. Structural insights into the cPLA2α preference for phosphatidylcholine (PC)-enriched membranes have remained elusive. Here, we report cPLA2α C2-domain structure (2.2Å resolution) containing bound 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) and Ca2+ ions. Two Ca2+ are complexed at locations previously reported for lipid-free C2-domain. One of these Ca2+ along with a third Ca2+ bridge the C2-domain to the DHPC phosphate group, which also interacts with Asn65. Tyr96 plays a key role in lipid headgroup recognition via cation-π interaction with the PC trimethylammonium group. Mutagenesis analyses confirm Tyr96 and Asn65 function in PC binding selectivity by C2-domain and regulation of cPLA2α activity. The differing DHPC-binding mode of cPLA2α C2-domain, compared to phosphatidylserine or phosphatidylinositol 4,5-bisphosphate binding by other C2-domains, expands and deepens knowledge of lipid-binding mechanisms mediated by C2-domains.

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Diffraction data have been deposited in PDB under the accession code 6IEJ

The following data sets were generated

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Author details

  1. Yoshinori Hirano

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9888-1616

  2. Yong-Guang Gao

    Hormel Institute, University of Minnesota, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9359-4252

  3. Daniel J Stephenson

    Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5698-3400

  4. Ngoc T Vu

    Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Lucy Malinina

    Hormel Institute, University of Minnesota, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7973-1831

  6. Dhirendra K Simanshu

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9717-4618

  7. Charles E Chalfant

    Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5844-5235

  8. Dinshaw J Patel

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    The authors declare that no competing interests exist.

  9. Rhoderick E Brown

    Hormel Institute, University of Minnesota, Austin, United States
    For correspondence
    reb@umn.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7337-3604

Funding

National Institutes of Health (HL125353)

  • Rhoderick E Brown

Ministry of Education, Culture, Sports, Science, and Technology

  • Yoshinori Hirano

U.S. Department of Veterans Affairs (I BX001792)

  • Charles E Chalfant

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

Copyright

© 2019, Hirano 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. Yoshinori Hirano
  2. Yong-Guang Gao
  3. Daniel J Stephenson
  4. Ngoc T Vu
  5. Lucy Malinina
  6. Dhirendra K Simanshu
  7. Charles E Chalfant
  8. Dinshaw J Patel
  9. Rhoderick E Brown
(2019)
Structural basis of phosphatidylcholine recognition by the C2-domain of cytosolic phospholipase A2α
eLife 8:e44760.
https://doi.org/10.7554/eLife.44760

Share this article

https://doi.org/10.7554/eLife.44760

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