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Using Ex Vivo Live Imaging to Investigate Cell Divisions and Movements During Mouse Dental Renewal
Published on: October 27, 2023
Ring1a/b polycomb proteins regulate the mesenchymal stem cell niche in continuously growing incisors
Puangwan Lapthanasupkul1, Jifan Feng, Andrea Mantesso
1Department of Craniofacial Development, Dental Institute, King's College London, London SE1 9RT, United Kingdom.
Developmental Biology
|May 8, 2012
Summary
Polycomb repressive complex 1 (PRC1) proteins are crucial for mouse incisor development. Loss of Ring1a/b impairs dental stem cell niches, affecting tooth growth and molar root formation.
Area of Science:
- Developmental Biology
- Stem Cell Biology
- Epigenetics
Background:
- Rodent incisors grow continuously, maintained by stem cells in the cervical loop.
- The dental mesenchymal stem cell niche is less understood than the epithelial counterpart.
- Polycomb repressive complex 1 (PRC1) proteins, including Ring1a/b, are involved in gene regulation.
Purpose of the Study:
- To investigate the role of Ring1a/b and PRC1 in the dental mesenchymal stem cell niche.
- To characterize the effects of Ring1a/b loss on incisor development and cell proliferation.
- To explore the requirement of Ring1 proteins in molar root formation.
Main Methods:
- Analysis of Ring1a(-/-);Ring1b(cko/cko) mice with targeted gene deletion.
- Assessment of cell proliferation in incisor apical mesenchyme and cervical loop epithelium.
- Evaluation of gene expression, including Fgf signaling pathways.
Main Results:
- Loss of Ring1a/b leads to defective cervical loops and abnormal enamel/dentin formation.
- Cell proliferation is significantly reduced in the apical mesenchyme and cervical loop epithelium of mutant mice.
- Fgf signaling is downregulated, and PRC1 gene expression is altered in Ring1a/b-deficient incisors.
- Ring1 proteins are essential for postnatal molar root formation.
Conclusions:
- PRC1 complex, regulated by Ring1a/b, is vital for the transit amplifying cell compartment in the dental mesenchymal stem cell niche.
- Ring1a/b are critical for cell differentiation in developing mouse incisors.
- Ring1 proteins play an essential role in molar root development.
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