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Updated: May 14, 2026
04:07
Isolation of Epithelial Cells from Human Dental Follicle
Published on: November 5, 2021
Ameloblastin in Hertwig's epithelial root sheath regulates tooth root formation and development
Naoto Hirose1, Atsushi Shimazu, Mineo Watanabe
1Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima, Japan. hirose@hiroshima-u.ac.jp
Plos One
|February 2, 2013
Summary
Ameloblastin (AMBN) is crucial for tooth root development. Inhibiting AMBN in mice led to shorter roots and altered Hertwig's epithelial root sheath (HERS) cell behavior, suggesting AMBN triggers normal root formation.
Area of Science:
- Dental Biology
- Developmental Biology
- Cell Biology
Background:
- Tooth root formation follows crown development, involving Hertwig's epithelial root sheath (HERS).
- Ameloblastin (AMBN), an enamel matrix protein, is present in HERS, but its role in root formation is not fully understood.
Purpose of the Study:
- To investigate the function of Ameloblastin (AMBN) in tooth root formation.
- To elucidate the mechanism by which AMBN influences HERS cell behavior during root development.
Main Methods:
- Localization of AMBN in mouse lower first molar HERS.
- In vivo experiments using small interfering RNA (siRNA) targeting AMBN in developing mouse molars.
- In vitro studies assessing the effects of AMBN expression on HERS-derived cells.
Main Results:
- AMBN was detected in the basal portion of HERS, not the tip.
- AMBN siRNA injection resulted in shorter tooth roots and a multilayered HERS with increased proliferation (BrdU positive cells).
- In vitro, absence of AMBN enhanced growth suppressor genes (p21, p27) and increased BrdU incorporation.
Conclusions:
- AMBN expression in HERS is essential for normal tooth root formation.
- AMBN appears to regulate the differentiation and proliferation of HERS-derived cells, influencing root elongation.
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