An Eya1-Notch axis specifies bipotential epibranchial differentiation in mammalian craniofacial morphogenesis
Abstract
Craniofacial morphogenesis requires proper development of pharyngeal arches and epibranchial placodes. We show that the epibranchial placodes, in addition to giving rise to cranial sensory neurons, generate a novel lineage-related non-neuronal cell population for mouse pharyngeal arch development. Eya1 is essential for the development of epibranchial placodes and proximal pharyngeal arches. We identify an Eya1-Notch regulatory axis that specifies both the neuronal and non-neuronal commitment of the epibranchial placode, where Notch acts downstream of Eya1 and promotes the non-neuronal cell fate. Notch is regulated by the threonine phosphatase activity of Eya1. Eya1 dephosphorylates p-threonine-2122 of the Notch1 intracellular domain (Notch1 ICD), which increases the stability of Notch1 ICD and maintains Notch signaling activity in the non-neuronal epibranchial placodal cells. Our data unveil a more complex differentiation program in epibranchial placodes and an important role for the Eya1-Notch axis in craniofacial morphogenesis.
Article and author information
Author details
Funding
Research Grants Council, University Grants Committee (RGC GRF 777411)
- Mai Har Sham
Research Grants Council, University Grants Committee (RGC GRF 17113415)
- Mai Har Sham
Cancerfonden (SCS X2017-2019,335)
- Urban Lendahl
Vetenskapsrådet (project grant 2014-2018,RX331)
- Urban Lendahl
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 mouse experiments were performed in strict accordance with the recommendations and approved by the University of Hong Kong animal research ethics committee (CULATR No. 3329-14 and 3862-15).
Version history
- Received: July 3, 2017
- Accepted: November 13, 2017
- Accepted Manuscript published: November 15, 2017 (version 1)
- Version of Record published: November 28, 2017 (version 2)
Copyright
© 2017, Zhang 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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