Highly-regulated, diversifying NTP-based biological conflict systems with implications for emergence of multicellularity

  1. Gurmeet Kaur
  2. A Maxwell Burroughs
  3. Lakshminarayan M Iyer
  4. L Aravind  Is a corresponding author
  1. National Institutes of Health, United States

Abstract

Social cellular aggregation or multicellular organization pose increased risk of transmission of infections through the system upon infection of a single cell. The generality of the evolutionary responses to this outside of Metazoa remains unclear. We report the discovery of several thematically-unified, remarkable biological conflict systems preponderantly present in multicellular prokaryotes. These combine thresholding mechanisms utilizing NTPase chaperones (the MoxR-vWA couple), GTPases and proteolytic cascades with hypervariable effectors, which vary either by using a reverse transcriptase-dependent diversity-generating system or through a system of acquisition of diverse protein modules, typically in inactive form, from various cellular subsystems. Conciliant lines of evidence indicate their deployment against invasive entities, like viruses, to limit their spread in multicellular/social contexts via physical containment, dominant-negative interactions or apoptosis. These findings argue for both a similar operational 'grammar' and shared protein domains in the sensing and limiting of infections during the multiple emergences of multicellularity.

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All data generated or analysed during this study are included in the manuscript and supporting files.

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Author details

  1. Gurmeet Kaur

    Computational Biology Branch, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. A Maxwell Burroughs

    Computational Biology Branch, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2229-8771
  3. Lakshminarayan M Iyer

    Computational Biology Branch, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. L Aravind

    National Center for Biotechnology Information, National Institutes of Health, Bethesda, United States
    For correspondence
    aravind@ncbi.nlm.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0771-253X

Funding

National Institutes of Health (Intramural Research Program)

  • Gurmeet Kaur
  • A Maxwell Burroughs
  • Lakshminarayan M Iyer
  • L Aravind

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

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Gurmeet Kaur
  2. A Maxwell Burroughs
  3. Lakshminarayan M Iyer
  4. L Aravind
(2020)
Highly-regulated, diversifying NTP-based biological conflict systems with implications for emergence of multicellularity
eLife 9:e52696.
https://doi.org/10.7554/eLife.52696

Share this article

https://doi.org/10.7554/eLife.52696

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