STING mediates immune responses in the closest living relatives of animals

  1. Arielle Woznica  Is a corresponding author
  2. Ashwani Kumar
  3. Carolyn R Sturge
  4. Chao Xing
  5. Nicole King
  6. Julie K Pfeiffer  Is a corresponding author
  1. UT Southwestern Medical Center, United States
  2. Howard Hughes Medical Institute, University of California, Berkeley, United States

Abstract

Animals have evolved unique repertoires of innate immune genes and pathways that provide their first line of defense against pathogens. To reconstruct the ancestry of animal innate immunity, we have developed the choanoflagellate Monosiga brevicollis, one of the closest living relatives of animals, as a model for studying mechanisms underlying pathogen recognition and immune response. We found that M. brevicollis is killed by exposure to Pseudomonas aeruginosa bacteria. Moreover, M. brevicollis expresses STING, which, in animals, activates innate immune pathways in response to cyclic dinucleotides during pathogen sensing. M. brevicollis STING increases the susceptibility of M. brevicollis to P. aeruginosa-induced cell death and is required for responding to the cyclic dinucleotide 2'3' cGAMP. Furthermore, similar to animals, autophagic signaling in M. brevicollis is induced by 2'3' cGAMP in a STING-dependent manner. This study provides evidence for a pre-animal role for STING in antibacterial immunity and establishes M. brevicollis as a model system for the study of immune responses.

Data availability

Raw sequencing reads and normalized gene counts have been deposited at the NCBI GEO under accession GSE174340

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

Article and author information

Author details

  1. Arielle Woznica

    UT Southwestern Medical Center, Dallas, United States
    For correspondence
    Arielle.Woznica@UTSouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Ashwani Kumar

    UT Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Carolyn R Sturge

    UT Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6596-3356
  4. Chao Xing

    UT Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1838-0502
  5. Nicole King

    Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Julie K Pfeiffer

    UT Southwestern Medical Center, Dallas, United States
    For correspondence
    Julie.Pfeiffer@UTSouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2973-4895

Funding

Howard Hughes Medical Institute (Hanna Gray Fellows Program)

  • Arielle Woznica

Howard Hughes Medical Institute (Faculty Scholars Program)

  • Julie K Pfeiffer

Howard Hughes Medical Institute

  • Nicole King

Pew Charitable Trusts (Pew Innovation Fund)

  • Nicole King
  • Julie K Pfeiffer

Burroughs Wellcome Fund (Investigators in the Pathogenesis of Infectious Diseases)

  • Julie K Pfeiffer

National Cancer Institute (1P30 CA142543)

  • Arielle Woznica
  • Julie K Pfeiffer

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

Reviewing Editor

  1. Sara Cherry, University of Pennsylvania, United States

Version history

  1. Preprint posted: May 14, 2021 (view preprint)
  2. Received: May 17, 2021
  3. Accepted: November 2, 2021
  4. Accepted Manuscript published: November 3, 2021 (version 1)
  5. Version of Record published: November 15, 2021 (version 2)

Copyright

© 2021, Woznica 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. Arielle Woznica
  2. Ashwani Kumar
  3. Carolyn R Sturge
  4. Chao Xing
  5. Nicole King
  6. Julie K Pfeiffer
(2021)
STING mediates immune responses in the closest living relatives of animals
eLife 10:e70436.
https://doi.org/10.7554/eLife.70436

Share this article

https://doi.org/10.7554/eLife.70436

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