Craniofacial transitions: the role of EMT and MET during head development

Within the developing head, tissues undergo cell-fate transitions to shape the forming structures. This starts with the neural crest, which undergoes epithelial-to-mesenchymal transition (EMT) to form, amongst other tissues, many of the skeletal tissues of the head. In the eye and ear, these neural crest cells then transform back into an epithelium, via mesenchymal-to-epithelial transition (MET), highlighting the flexibility of this population. Elsewhere in the head, the epithelium loses its integrity and transforms into mesenchyme. Here, we review these craniofacial transitions, looking at why they happen, the factors that trigger them, and the cell and molecular changes they involve. We also discuss the consequences of aberrant EMT and MET in the head.

Automated summary

During head development, tissues undergo cell fate transitions to form structures, where neural crest cells play a crucial role in shaping skeletal tissues. These cells exhibit flexibility in transitioning back and forth between epithelial and mesenchymal states in the eye and ear. Understanding the factors triggering these transitions and the consequences of aberrant transitions is important for studying craniofacial development.