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Analysis of Developing Tooth Germ Innervation Using Microfluidic Co-culture Devices
Published on: August 14, 2015
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The initiation knot is a signaling center required for molar tooth development
Isabel Mogollón1, Jacqueline E Moustakas-Verho1,2, Minna Niittykoski1
1Cell and Tissue Dynamics Research Program, Institute of Biotechnology, University of Helsinki, 00014, Finland.
Development (Cambridge, England)
|April 29, 2021
Summary
A newly identified early signaling center, the molar initiation knot (IK), is crucial for mammalian tooth development. This discovery reveals that iterative signaling centers drive tooth formation from initiation through patterning.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- Signaling centers regulate embryonic morphogenesis.
- Enamel knots (EKs) are known signaling centers for mammalian molar tooth patterning.
- The role of a preceding transient epithelial thickening is debated.
Purpose of the Study:
- To investigate the significance of the transient epithelial thickening before the primary enamel knot.
- To identify and characterize this early structure as a signaling center.
- To understand its role in tooth development progression.
Main Methods:
- Tissue confocal fluorescence imaging.
- Laser ablation experiments.
- Analysis of cell cycle exit, condensation, and apoptosis.
Main Results:
- The transient thickening is identified as the molar initiation knot (IK), an early signaling center.
- IK exhibits hallmarks of signaling centers: cell cycle exit, condensation, and apoptosis.
- IK initiation involves Wnt activity juxtaposed with Shh-expressing cells, driving tooth bud growth and primary EK formation.
Conclusions:
- The molar initiation knot (IK) is essential for the progression of tooth development.
- Tooth development, from initiation to patterning, relies on the iterative function of signaling centers.
- This study elucidates a novel signaling center's role in early tooth morphogenesis.
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