Emx2 regulates hair cell rearrangement but not positional identity within neuromasts
- 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.
Article and author information
Author details
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.
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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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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