1. Developmental Biology
  2. Evolutionary Biology
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Par protein localization during the early development of Mnemiopsis leidyi suggests different modes of epithelial organization in the Metazoa

  1. Miguel Salinas-Saavedra  Is a corresponding author
  2. Mark Q Martindale  Is a corresponding author
  1. National University of Ireland Galway, Ireland
  2. University of Florida, United States
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Cite this article as: eLife 2020;9:e54927 doi: 10.7554/eLife.54927


In bilaterians and cnidarians, epithelial cell-polarity is regulated by the interactions between Par proteins, Wnt/PCP signaling pathway, and cell-cell adhesion. Par proteins are highly conserved across Metazoa, including ctenophores. But strikingly, ctenophore genomes lack components of the Wnt/PCP pathway and cell-cell adhesion complexes raising the question if ctenophore cells are polarized by mechanisms involving Par proteins. Here, by using immunohistochemistry and live-cell imaging of specific mRNAs, we describe for the first time the subcellular localization of selected Par proteins in blastomeres and epithelial cells during the embryogenesis of the ctenophore Mnemiopsis leidyi. We show that these proteins distribute differently compared to what has been described for other animals, even though they segregate in a host-specific fashion when expressed in cnidarian embryos. This differential localization might be related to the emergence of different junctional complexes during metazoan evolution.

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Author details

  1. Miguel Salinas-Saavedra

    Centre for Chromosome Biology, National University of Ireland Galway, Galway, Ireland
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1598-9881
  2. Mark Q Martindale

    Whitney laboratory, University of Florida, Saint Augustine, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.


National Science Foundation (NSF IOS-1755364)

  • Mark Q Martindale

National Aeronautics and Space Administration (NASA 16-EXO16_2-0041)

  • Mark Q Martindale

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

Reviewing Editor

  1. Patricia J Wittkopp, University of Michigan, United States

Publication history

  1. Received: January 6, 2020
  2. Accepted: July 23, 2020
  3. Accepted Manuscript published: July 27, 2020 (version 1)
  4. Accepted Manuscript updated: July 30, 2020 (version 2)


© 2020, Salinas-Saavedra & Martindale

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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