Project description:RNAseq was employed to profile taste progenitors (SOX2-GFPhigh) and non-taste epithelial progenitors (SOX2-GFPlow) at the onset of taste cell renewal at birth. This dataset was acquired via FACS of SOX2-GFP+ epithelial cells from SOX2gfp/+ mouse pups at P0.
Project description:Embryonic taste bud primordia are specified as taste placodes on the tongue surface and differentiate into the first taste receptor cells (TRCs) at birth. Throughout adult life, TRCs are continually regenerated from epithelial progenitors. Sonic hedgehog (SHH) signaling regulates TRC development and renewal, repressing taste fate embryonically, but promoting TRC differentiation in adults. Here, using mouse models, we show TRC renewal initiates at birth and coincides with onset of SHHs pro-taste function. Using transcriptional profiling to explore molecular regulators of renewal, we identified Foxa1 and Foxa2 as potential SHH target genes in lingual progenitors at birth and show that SHH overexpression in vivo alters FoxA1 and FoxA2 expression relevant to taste buds. We further bioinformatically identify genes relevant to cell adhesion and cell locomotion likely regulated by FOXA1;FOXA2 and show that expression of these candidates is also altered by forced SHH expression. We present a new model where SHH promotes TRC differentiation by regulating changes in epithelial cell adhesion and migration.
Project description:Taste stem/progenitor cells from the mouse posterior tongue have been recently used to generate taste bud organoids. However, the inaccessible location of the taste receptor cells is observed in conventional organoids. Here, we established a suspension culture method for fine tuning of taste bud organoid by apicobasal polarity alteration to form the accessible localization of taste receptor cells in organoid. Compared to conventional Matrigel-embedded organoids, suspension-cultured organoids showed comparable differentiation and renewal rates to those of taste buds in vivo and exhibited functional taste receptor cells and cycling progenitor cells. Accessible taste receptor cells on the outer region of taste bud organoids enabled the direct application of calcium imaging for evaluating the taste response. Moreover, suspension-cultured organoids could be genetically altered using gene editing methods. Suspension-cultured taste bud organoid harmoniously integrated with the recipient lingual epithelium; maintained the taste receptor cells and gustatory innervation capacity. Thus, we propose that suspension-cultured organoids may provide efficient model for taste research including taste bud development, regeneration and transplantation
Project description: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.
Project description:To uncover novel molecules involved in taste detection, we performed a microarray-based screen for genes enriched in taste neurons. Proboscis RNA from flies homozygous for a recessive poxn null mutation was compared to RNA from heterozygous controls. Poxn mutants have a transformation of labellar gustatory chemosensory bristles into mechanosensory bristles and therefore lack most or all taste neurons. Experiment Overall Design: Proboscises of poxn70 homozygous mutant and poxn70 heterozygous mutant males (8-18 days post eclosure) were dissected, and total RNA was harvested in Trizol according to standard trizol protocol. Samples for each microarray were prepared from 164-280 proboscises. We performed 3 biological replicates for each genotype.
Project description:Previously we showed that taste receptor cells in situ in taste buds synthesize insulin. Here we describe a model of pig taste organoid culture in which we have promoted insulin expression by induction of quiescence. The cellular heterogeneity of the lingual epithelium is maintained in the organoids, and stem cell type and organoid architecture can be controlled through changes in media composition and/or use of static versus dynamic culture. Pig taste organoids were maintained long term and organoids cultured in low sheer stress dynamic exhibited an architecture and expression profile akin to the native tissue. Porcine taste organoids also contained insulin, and the insulin critical transcription factors MAFA and PAX4. These results provide a pig model of taste organoid culture that can be used universally and bring us closer to the use of the taste tissue as a new renewable source of beta cells
Project description:The circumvallate papillae (CVP) and foliate papillae (FoP) of the posterior tongue contain taste buds in close proximity to specialized salivary glands, known as von Ebner and minor salivary glands, respectively. The developmental relationship between taste buds and these salivary glands remains largely unexplored. Lineage tracing studies in mice have revealed that Lgr5 marks taste bud stem cells. Here, we report single-cell RNA sequencing of the entire CVP and FoP of mice, yielding transcriptional profiles of cells from tongue surface epithelium, taste buds and the associated salivary glands. We unveiled a developmental trajectory in which taste buds, the associated salivary glands and the non-taste tongue surface epithelium originate from a common Lgr5+ cell. We describe long-term organoid culture conditions for these cells and confirm their tripotency at the clonal level in vitro. CVP and FoP harbor chemosensory units consisting of taste bud and salivary gland cells derived from the same parental Lgr5+ stem cell.