Shaping of inner ear sensory organs through antagonistic interactions between Notch signalling and Lmx1a
Abstract
The mechanisms of formation of the distinct sensory organs of the inner ear and the non-sensory domains that separate them are still unclear. Here, we show that several sensory patches arise by progressive segregation from a common prosensory domain in the embryonic chicken and mouse otocyst. This process is regulated by mutually antagonistic signals: Notch signalling and Lmx1a. Notch-mediated lateral induction promotes prosensory fate. Some of the early Notch-active cells, however, are normally diverted from this fate and increasing lateral induction produces misshapen or fused sensory organs in the chick. Conversely Lmx1a (or cLmx1b in the chick) allows sensory organ segregation by antagonizing lateral induction and promoting commitment to the non-sensory fate. Our findings highlight the dynamic nature of sensory patch formation and the labile character of the sensory-competent progenitors, which could have facilitated the emergence of new inner ear organs and their functional diversification in the course of evolution.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/L003163/1 Project grant)
- Zoe F Mann
- Nicolas Daudet
Action on Hearing Loss (G76 Postdoc grant)
- Magdalena Żak
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Marianne Bronner, California Institute of Technology, United States
Ethics
Animal experimentation: All experimental procedures were carried out in accordance with the United Kingdom Scientific Procedures Act of 1986. All animals were handled according to protocols covered by a Home Office Animal Procedures Licence (PPL 70/8144) and approved by University College London local Ethics Committee.
Version history
- Received: November 3, 2017
- Accepted: December 2, 2017
- Accepted Manuscript published: December 4, 2017 (version 1)
- Version of Record published: December 11, 2017 (version 2)
Copyright
© 2017, Mann 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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