Possible Linkage of SP6 Transcriptional Activity with Amelogenesis by Protein Stabilization

Figure 5

Proposed model of Sp6 expression and function coupled with amelogenesis in dental epithelial cells. BMP and Wnt signals can enhance Sp6 promoter activity, resulting in the enhancement of Sp6 mRNA expression (6). The level of SP6 protein expression is regulated by proteasome activity, which would be physiologically controlled by a MG132-equivalent factor X. Stabilized SP6 protein is transferred into the nucleus and regulates the expression of amelotin and rock1 mRNA. BRE: BMP signal-responsive elements; WRE: Wnt signal-responsive elements.