J Korean Dent Sci.  2016 Jun;9(1):9-18. 10.5856/JKDS.2016.9.1.9.

The Role of Autonomous Wntless in Odontoblastic Differentiation of Mouse Dental Pulp Cells

• Choi H
• Kim TH
• Ko SO
• Cho ES

• KMID: 2382973
• DOI: http://doi.org/10.5856/JKDS.2016.9.1.9

Abstract

PURPOSE
Wnt signaling plays an essential role in the dental epithelium and mesenchyme during tooth morphogenesis. Deletion of the Wntless (Wls) gene in odontoblasts appears to reduce canonical Wnt activity, leading to inhibition of odontoblast maturation. However, it remains unclear if autonomous Wnt ligands are necessary for differentiation of dental pulp cells into odontoblast-like cells to induce reparative dentinogenesis, one of well-known feature of pulp repair to form tertiary dentin.
MATERIALS AND METHODS
To analyze the autonomous role of Wls for differentiation of dental pulp cells into odontoblast-like cells, we used primary dental pulp cells from unerupted molars of Wls-floxed allele mouse after infection with adenovirus for Cre recombinase expression to knockout the floxed Wls gene or control GFP expression. The differentiation of dental pulp cells into odontoblast-like cells was analyzed by quantitative real-time polymerase chain reaction. RESULT: Proliferation rate was significantly decreased in dental pulp cells with Cre expression for Wls knockout. The expression levels of Osterix (Osx), runt-related transcription factor 2 (Runx2), and nuclear factor I-C (Nfic) were all significantly decreased by 0.3-fold, 0.2-fold, and 0.3-fold respectively in dental pulp cells with Wls knockout. In addition, the expression levels of Bsp, Col1a1, Opn, and Alpl were significantly decreased by 0.7-fold, 0.3-fold, 0.8-fold, and 0.6-fold respectively in dental pulp cells with Wls knockout.
CONCLUSION
Wnt ligands produced autonomously are necessary for proper proliferation and odontoblastic differentiation of mouse dental pulp cells toward further tertiary dentinogenesis.

Keyword

Dental pulp; Reparative dentin; Wntless

MeSH Terms

Adenoviridae
Alleles
Animals
Dental Pulp*
Dentin
Dentinogenesis
Epithelium
Ligands
Mesoderm
Mice*
Molar
Morphogenesis
NFI Transcription Factors
Odontoblasts*
Real-Time Polymerase Chain Reaction
Recombinases
Tooth
Transcription Factors
Ligands
NFI Transcription Factors
Recombinases
Transcription Factors