Bioinformatics Database

The role of Tumor necrosis factor (TNF)-family in tooth morphogenesis is well-known, indicating that the pathway, that activate NF-kappaB, is important in the development of tooth number and shape (Ohazama & Sharpe, 2004).

Tumor necrosis factor receptor-associated factors (TRAFs) belong to a family of intracellular adaptor proteins mediating signals downstream of cell surface receptors. Ohazama et al. (2003) conducted a comparative in situ hybridization analysis of five Traf genes Traf1, Traf2, Traf3, Traf4 and Traf6 during murine odontogenesis in differnt tooth developmental stages. Their results showed that Traf2, Traf3 and Traf6 ware weakly expressed in the thickened epithelium. Expression of Traf1, Traf2 and Traf6 were observed in the outer edges of the bud epithelium whereas Traf3 was strongly expressed at the tip of the bud epithelium. Expression of Traf1, Traf4 and Traf6 were detected in the dental papilla mesenchyme. Traf2 showed restricted expression in the internal enamel epithelium of the bell stage while expression of Traf1, Traf3, Traf4 and Traf6 were observed in both the internal and the external enamel epithelium.