P9-reduced expression of tight junction proteins ZO-1 and Claudin-1 in ameloblasts and odontoblasts of Epiprofin/Sp6 deficient mice.

Introduction Odontoblasts and ameloblasts are columnar cells that characterize by a highly polarized distribution of organelles. Junctional complexes and the cytoskeleton are important in maintaining ameloblast and odontoblast cell polarity and cell-cell interactions. In addition, cell adhesion is a key regulator of gene expression and cell differentiation. Tight junction binding proteins proteins such as Zonnula Occludens-1 (ZO-1) and the Ybox transcription factor ZONAB (ZO-1 associated Nucleic Acid Binding protein) can be either recruited to tight junctions or alternatively translocated to the nucleus, where they act to upregulate expression of genes involved in cell proliferation and differentiation (1).