Emx2 regulates hair cell rearrangement but not positional identity within neuromasts

  1. Sho Ohta
  2. Young Rae Ji
  3. Daniel Martin
  4. Doris K Wu  Is a corresponding author
  1. NIDCD, NIH, United States

Abstract

Each hair cell (HC) precursor of zebrafish neuromasts divides to form two daughter HCs of opposite hair bundle orientations. Previously, we showed that transcription factor Emx2, expressed in only one of the daughter HCs, generates this bidirectional HC pattern (Jiang et al., 2017). Here, we asked whether Emx2 mediates this effect by changing location of hair bundle establishment or positions of HCs since daughter HCs are known to switch positions with each other. We showed this HC rearrangement, redefined as two processes named Rock & Roll, is required for positional acquisition of HCs. Apical protrusion formation of nascent HCs and planar polarity signaling are both important for the Rock & Roll. Emx2 facilitates Rock & Roll by delaying apical protrusion of its nascent HCs but it does not determine HCs' ultimate positions, indicating that Emx2 mediates bidirectional HC pattern by changing the location where hair bundle is established in HCs.

Data availability

Sequencing data have been deposited in GEO under accession code GSE152859.

The following data sets were generated

Article and author information

Author details

  1. Sho Ohta

    Lab of Molecular Biology, NIDCD, NIH, Bethesda, United States
    Competing interests
    No competing interests declared.
  2. Young Rae Ji

    Section on Sensory Cell Regeneration and Development, Laboratory of Molecular Biology, NIDCD, NIH, Bethesda, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8825-9783
  3. Daniel Martin

    Genomics and Computational Biology Core, NIDCD, NIH, Bethesda, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8880-9087
  4. Doris K Wu

    Section on Sensory Cell Regeneration and Development, Laboratory of Molecular Biology, NIDCD, NIH, Bethesda, United States
    For correspondence
    wud@nidcd.nih.gov
    Competing interests
    Doris K Wu, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1400-3558

Funding

National Institutes of Health (1ZIADC000021)

  • Doris K Wu

National Institutes of Health (ZICDC000086)

  • Daniel Martin

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

Ethics

Animal experimentation: All zebrafish experiments were conducted according to NIH approved animal protocol (#1362-13) and NIH animal user guidelines.

Reviewing Editor

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

Publication history

  1. Received: July 1, 2020
  2. Accepted: December 29, 2020
  3. Accepted Manuscript published: December 30, 2020 (version 1)
  4. Version of Record published: January 13, 2021 (version 2)

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. Sho Ohta
  2. Young Rae Ji
  3. Daniel Martin
  4. Doris K Wu
(2020)
Emx2 regulates hair cell rearrangement but not positional identity within neuromasts
eLife 9:e60432.
https://doi.org/10.7554/eLife.60432

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