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Published on: October 27, 2023
MAPK mediates Hsp25 signaling in incisor development.
Min-Jung Lee1, Jinglei Cai, Sung-Wook Kwak
1Department of Oral Biology, College of Dentistry, Yonsei Center of Biotechnology, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul, 120-752, Korea.
Histochemistry and Cell Biology
|February 20, 2009
Summary
Mitogen-activated protein kinase (MAPK) signaling is crucial for mouse incisor development and ameloblast differentiation. Inhibiting MAPK pathways with U0126 blocked key signaling events, highlighting MAPK
Area of Science:
- * Developmental Biology
- * Molecular Biology
- * Dental Research
Background:
- * Rodent incisors exhibit continuous amelogenesis, offering a model to study tooth development.
- * Mitogen-activated protein kinase (MAPK) signaling pathways, including extracellular-signal regulated kinase (ERK)/MAPK kinase (MEK), are implicated in cell cycle and survival.
- * Heat-shock protein (Hsp)-25 serves as a marker for odontoblast differentiation, but its role in incisor development requires clarification.
Purpose of the Study:
- * To investigate the role of MAPK signaling in mouse incisor development and growth.
- * To elucidate the involvement of MAPK signaling in Hsp25 expression and signaling during incisor formation.
- * To determine the effects of MAPK activation and inhibition on incisor ameloblasts.
Main Methods:
- * Immunohistochemistry was used to localize phospho-ERK (pERK), pMEK, and Hsp25 in developing mouse incisors.
- * In vitro culture of incisor tooth germ was performed.
- * Anisomycin (MAPK activator) and U0126 (MAPK inhibitor) were applied to study MAPK signaling.
- * Western blotting was employed to analyze protein phosphorylation and expression.
Main Results:
- * pERK, pMEK, and Hsp25 were localized in the ameloblasts of developing mouse incisors.
- * Anisomycin treatment did not promote incisor development but stimulated phosphorylation of ERK, MEK, and Hsp25.
- * U0126 inhibited the phosphorylation of ERK, MEK, and Hsp25, indicating MAPK pathway involvement.
- * Anisomycin-induced signaling was partially blocked by U0126.
Conclusions:
- * MAPK signaling pathways are essential for mouse incisor formation, differentiation, and development.
- * MAPK signaling regulates Hsp25 expression and function during amelogenesis.
- * Targeting MAPK pathways could offer insights into controlling tooth development and regeneration.
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