Project description:Efforts to unravel the mechanisms underlying taste sensation (gustation) have largely focused on rodents. The first comprehensive database of gene expression in primate (Macaca fascicularis) taste buds is presented. This database provides a foundation for further studies in diverse aspects of taste biology. A taste bud gene expression database was generated using laser capture microdissection (LCM) of tissue freeze medium OTC embedded macaque tongue tissue blocks. We collected fungiform (FG) taste buds at the front of the tongue, circumvallate (CV) taste buds at the back of the tongue, as well as non-gustatory lingual epithelium (LE). Gene expression was also analyzed in the top and bottom portions of CV taste buds collected using LCM. Samples were collected from 10 animals - 7 female, 3 male.
Project description:Taste buds on the tongue are collections of taste receptor cells (TRCs) that detect sweet, sour, salty, umami and bitter stimuli. Like non-taste lingual epithelium, TRCs are renewed from basal keratinocytes, many of which express the transcription factor SOX2. Genetic lineage tracing has shown SOX2+ lingual progenitors give rise to both taste and non-taste lingual epithelium in the posterior circumvallate taste papilla (CVP) of mice. However, SOX2 is variably expressed among CVP cells suggesting that their progenitor potential may vary. Using transcriptome analysis and organoid technology, we show highly expressing SOX2+ cells are taste-competent progenitors that give rise to organoids comprising both TRCs and lingual epithelium, while organoids derived from low-expressing SOX2+ progenitors are composed entirely of non-taste cells. Hedgehog and WNT/ß-catenin are required for taste homeostasis in adult mice, but only WNT/ß-catenin promotes TRC differentiation in vitro and does so only in organoids derived from higher SOX2+ taste lineage-competent progenitors.
Project description:In this study, we used RNA sequencing to characterize a new population of taste buds found in the esophagus and compared them to their lingual counterpart. We concluded that esophageal taste buds share many markers with lingual taste buds althoug they seem to express less taste receptors in average.
Project description:In this study, we uncovered through single cell RNA sequencing (scRNA-seq) of mouse esophagus epithelium a population of taste buds clustered in the cervical segment of the esophagus. We compared this taste bud population to their lingual counterpart. We concluded that these taste buds have the same cellular composition than the ones from the tongue. State-of-the-art transcriptional regulatory network analysis allowed the identification of specific transcription factors associated to the differentiation of immature progenitors into the three different taste bud cell types in the tongue and the esophagus.
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: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:Infinium 450K is a hybridization array designed for the human genome, but the relative conservation between the macaque and human genomes makes its use in macaques feasible. We used the Infinium450K array to assay twelve Cynomolgus macaque muscle biopsies and compared it to Reduced Representation Bisulphite Sequencing (RRBS) data generated on the same samples. Muscle biopsies were performed on eleven adult male cynomologus macaques