Abstract

Transport of fluids, molecules, nutrients or nanoparticles through coral tissues are poorly documented. Here, we followed the flow of various tracers from the external seawater to within the cells of all tissues in living animals. After entering the general coelenteric cavity, we show that nanoparticles disperse throughout the tissues via the paracellular pathway. Then, the ubiquitous entry gate to within the cells' cytoplasm is macropinocytosis. Most cells form large vesicles of 350-600 nm in diameter at their apical side, continuously internalizing their surrounding medium. Macropinocytosis was confirmed using specific inhibitors of PI3K and actin polymerization. Nanoparticle internalization dynamics is size dependent and differs between tissues. Furthermore, we reveal that macropinocytosis is likely a major endocytic pathway in other anthozoan species. The fact that nearly all cells of an animal are continuously soaking in the environment challenges many aspects of the classical physiology viewpoints acquired from the study of bilaterians.

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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. Philippe Ganot

    Biochemistry and physiology, Centre Scientifique de Monaco, Monaco, Monaco
    For correspondence
    pganot@centrescientifique.mc
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1743-9709
  2. Eric Tambutté

    Biochemistry and physiology, Centre Scientifique de Monaco, Monaco, Monaco
    Competing interests
    The authors declare that no competing interests exist.
  3. Natacha Caminiti-Segonds

    Biochemistry and physiology, Centre Scientifique de Monaco, Monaco, Monaco
    Competing interests
    The authors declare that no competing interests exist.
  4. Gaëlle Toullec

    Biochemistry and physiology, Centre Scientifique de Monaco, Monaco, Monaco
    Competing interests
    The authors declare that no competing interests exist.
  5. Denis Allemand

    Biochemistry and physiology, Centre Scientifique de Monaco, Monaco, Monaco
    Competing interests
    The authors declare that no competing interests exist.
  6. Sylvie Tambutté

    Marine Biology Department, Centre Scientifique de Monaco, Monaco, Monaco
    Competing interests
    The authors declare that no competing interests exist.

Funding

Government of the Principality of Monaco

  • Philippe Ganot
  • Eric Tambutté
  • Natacha Caminiti-Segonds
  • Gaëlle Toullec
  • Denis Allemand
  • Sylvie Tambutté

This work was supported by the Centre Scientifique de Monaco research program, funded by the Government of the Principality of Monaco.

Reviewing Editor

  1. María Isabel Geli, Institut de Biología Molecular de Barcelona (IBMB), Spain

Version history

  1. Received: July 8, 2019
  2. Accepted: February 8, 2020
  3. Accepted Manuscript published: February 10, 2020 (version 1)
  4. Version of Record published: February 20, 2020 (version 2)

Copyright

© 2020, Ganot 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. Philippe Ganot
  2. Eric Tambutté
  3. Natacha Caminiti-Segonds
  4. Gaëlle Toullec
  5. Denis Allemand
  6. Sylvie Tambutté
(2020)
Ubiquitous macropinocytosis in anthozoans
eLife 9:e50022.
https://doi.org/10.7554/eLife.50022

Share this article

https://doi.org/10.7554/eLife.50022

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