1. Cell Biology
  2. Developmental Biology and Stem Cells
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Eph and Ephrin function in dispersal and epithelial insertion of pigmented immunocytes in sea urchin embryos

  1. Oliver A Krupke
  2. Ivona Zysk
  3. Dan O Mellott
  4. Robert D Burke  Is a corresponding author
  1. University of Victoria, Canada
Research Article
  • Cited 6
  • Views 835
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Cite this article as: eLife 2016;5:e16000 doi: 10.7554/eLife.16000

Abstract

The mechanisms that underlie directional cell migration are incompletely understood. Eph receptors usually guide migrations of cells by exclusion from regions expressing Ephrin. In sea urchin embryos, pigmented immunocytes are specified in vegetal epithelium, transition to mesenchyme, migrate, and re-enter ectoderm, distributing in dorsal ectoderm and ciliary band, but not ventral ectoderm. Immunocytes express Sp-Eph and Sp-Efn is expressed throughout dorsal and ciliary band ectoderm. Interfering with expression or function of Sp-Eph results in rounded immunocytes entering ectoderm but not adopting a dendritic form. Expressing Sp-Efn throughout embryos permits immunocyte insertion in ventral ectoderm. In mosaic embryos, immunocytes insert preferentially in ectoderm expressing Sp-Efn. We conclude that Sp-Eph signaling is necessary and sufficient for epithelial insertion. As well, we propose that immunocytes disperse when Sp-Eph enhances adhesion, causing haptotactic movement to regions of higher ligand abundance. This is a distinctive example of Eph/Ephrin signaling acting positively to pattern migrating cells.

Article and author information

Author details

  1. Oliver A Krupke

    Department of Biology, University of Victoria, Victoria, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Ivona Zysk

    Department of Biochemistry and Microbiology, University of Victoria, Victoria, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Dan O Mellott

    Department of Biochemistry and Microbiology, University of Victoria, Victoria, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Robert D Burke

    Department of Biochemistry and Microbiology, University of Victoria, Victoria, Canada
    For correspondence
    rburke@uvic.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5527-4410

Funding

Natural Sciences and Engineering Research Council of Canada (2413-2009)

  • Robert D Burke

University of Victoria

  • Robert D Burke

Natural Sciences and Engineering Research Council of Canada (2016-03737)

  • Robert D Burke

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

Reviewing Editor

  1. Marianne E Bronner, California Institute of Technology, United States

Publication history

  1. Received: March 12, 2016
  2. Accepted: July 28, 2016
  3. Accepted Manuscript published: July 30, 2016 (version 1)
  4. Version of Record published: August 24, 2016 (version 2)

Copyright

© 2016, Krupke 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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