Eph/Ephrin Signaling Controls Progenitor Identities In The Ventral Spinal Cord
Julien Laussu1,2, Christophe Audouard1, Anthony Kischel1
1Centre de Biologie du Développement (CBD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 Route de Narbonne, 31062, Toulouse, France.
Neural Development
|June 10, 2017
Summary
Eph:ephrin signaling regulates motor neuron progenitor numbers in the vertebrate spinal cord. This signaling pathway is crucial for controlling progenitor identity during late-stage development, impacting motor neuron generation.
Area of Science:
- Developmental biology
- Neuroscience
- Cell signaling
Background:
- Motor neurons (MN) in the vertebrate spinal cord arise from a pool of dedicated progenitors (pMN).
- Regulation of pMN proliferation and differentiation is critical for establishing correct MN numbers.
- While pMN specification is understood, their number regulation over time remains less clear.
Purpose of the Study:
- To investigate the role of Eph:ephrin signaling in regulating motor neuron progenitor numbers.
- To understand how these signaling pathways influence progenitor identity during spinal cord development.
Main Methods:
- Differential expression analysis of ephrinB2, ephrinB3, and Eph receptors in the ventral spinal cord.
- Genetic loss-of-function analyses of ephrinB2 and ephrinB3.
- Immunostaining and phenotypic analysis.
- Genetic interaction studies with Shh.
Main Results:
- EphrinB2 and ephrinB3 are differentially expressed in progenitor domains.
- Genetic loss of ephrinB2/B3 inversely affects pMN numbers, correlating with MN numbers.
- Changes in pMN numbers in ephrin mutants result from altered progenitor identity at late developmental stages.
Conclusions:
- Eph:ephrin signaling is essential for maintaining progenitor identity in the ventral spinal cord.
- This signaling pathway plays a key role in the temporal regulation of motor neuron progenitor pools.
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