Developmental plasticity of epithelial stem cells in tooth and taste bud renewal

In Cichlids, replacement teeth (RT) share a continuous band of epithelium with adjacent taste buds (TB) and both organs co-express stem cell factors in subsets of label-retaining cells. In the mouse and other mammals, the tongue inter molar eminence (IE) oral papillae of Follistatin (Fat, BMP antagonist) mutants exhibited dysmorphic invagination. By using NGS-derived transcriptome profiling (RNAseq) analysis, we compared differential gene expression in the mouse tongue tissue in Follistatin (Fst) mutants mice with the wild type controls. Our results demonstrated ectopic expression of dental markers in tongue IE indicating that vertebrate oral epithelium retains inherent plasticity to form tooth and taste-like cell types mediated by BMP, therefore revealed under appreciated epithelial cell populations with promising potential in bioengineering and dental therapeutics. Overall design: Total RNA was extracted from mouse IE tissue at E17.5 in triplicate from Follistatin mutants and wild type mice. The mRNA profiles were generated by deep sequencing using Illumina Hiseq platform and the sequence reads that passed the quality filters were aligned with mouse mm10 reference genome by Partek workflows with default parameters. Aligned reads were annotated and normalized and differential gene expression was identify by GSA. Data analysis with BWA workflows revealed a number of potential differential tooth genes related to BMP signaling pathway that ectopically expressed in the tongue IE suggesting an evolutionary and developmental lineages of cells that function in oral organ systems may provide clues to their manipulation in regenerative medicine.