Project description:The organ development is dictated by the genes preferentially expressed in tissue or cell types uniquely. The clarification of gene expression profile and identification of specific genes in organ provide detailed understanding of organogenesis. Toward this purpose, the genome-wide analysis is a growing powerful tool for understanding development processes in organogenesis. Tooth is composed from enamel, dentin and cementum and these tissues are identical from other organs. The tooth-forming cell types are therefore unique and have complexed organization. The mechanisms of signal induction during tooth development is complicated because of the function of each cell types are still unclear. Previously, we performed the CAGE (Cap Analysis of Gene Expression) using mouse tooth germ to identify the genes preferentially expressed in tooth. The CAGE has advantage in quantification because it counts short reads of 5’ end without the bias of transcript length. Single-cell RNA-sequence (scRNA-seq) is a suitable tool revealing gene expression of each cells. The fundamental question of this study is how we can identify the tooth-specific and cell-type specific genes. In this study, we approach this using combination of scRNA-seq and CAGE (Cap Analysis of Gene Expression) as bioinformatics analyses. We obtained the scRNA-seq datasets of 12,212 cells from postnatal-day (P) 1 mouse molars, and the CAGE-seq datasets from P1 molars. scRNA-seq analysis revealed the spatio-temporal expression of tooth-related genes and CAGE determined whether these genes are truly tooth-specific or are expressed in ubiquitously. Furthermore, we identified candidate genes as novel tissue- and cell type- specific markers. Our results show that the integration of scRNA-seq and CAGE-seq improves the highlight genes important for tooth development from numerous gene profiles. These findings contribute resolving the mechanism of tooth development and establish the basis of tooth regeneration in future.
Project description:Throughout the various stages of tooth development, reciprocal epithelial-mesenchymal interactions are the driving force, for instance crucially involved in the differentiation of mature enamel-forming ameloblasts and dentin-producing odontoblasts. Here we established mouse tooth ‘assembloids’, comprised of tooth organoid-derived dental epithelial cells (from mouse molars and incisors) cultured together with molar dental pulp stem cells (DPSCs), to mimic these developmental interactions. Assembloids from both tooth types were grown both in basal- and differentiation-inducing conditions. Single cell transcriptomics analysis was applied to in detail characterize and validate the newly developed mouse tooth assembloid model and evaluate the induced differentiation processes.
Project description:To identify genes heretofore undiscovered as critical players in the biogenesis of teeth, we have used microarray gene expression analysis of the developing mouse molar tooth (DMT) between 1 and 10 days postnatal to identify genes differentially expressed when compared to 16 control tissues (GEO accession # GSE1986). Of the top 100 genes exhibiting increased expression in the DMT, 29 were found to have been previously associated with tooth development. Differential expression of the remaining 71 genes not previously associated with tooth development was confirmed by qRT-PCR analysis. Further analysis of seven of the latter genes by mRNA in situ hybridization found that five were specific to the developing tooth in the craniofacial region (Rspo4, Papln, Amtn, Gja1, Maf). Of the remaining two, one was found to be more widely expressed (Sp7) and the other was found to be specific to the nasal serous gland, which is close to, but distinct from, the developing tooth (Vrm). Keywords: tooth development
Project description:To identify genes heretofore undiscovered as critical players in the biogenesis of teeth, we have used microarray gene expression analysis of the developing mouse molar tooth (DMT) between 1 and 10 days postnatal to identify genes differentially expressed when compared to 16 control tissues (GEO accession # GSE1986). Of the top 100 genes exhibiting increased expression in the DMT, 29 were found to have been previously associated with tooth development. Differential expression of the remaining 71 genes not previously associated with tooth development was confirmed by qRT-PCR analysis. Further analysis of seven of the latter genes by mRNA in situ hybridization found that five were specific to the developing tooth in the craniofacial region (Rspo4, Papln, Amtn, Gja1, Maf). Of the remaining two, one was found to be more widely expressed (Sp7) and the other was found to be specific to the nasal serous gland, which is close to, but distinct from, the developing tooth (Vrm). Experiment Overall Design: mRNA from molar teeth extracted from Swiss Webster mouse pups between 1 and 10 days post-natal was pooled, labeled, and hybridized in quadruplicate to Affymetrix Mouse Genome Expression 430 2.0 microarrays. This data was compared to that of 16 control tissues (GEO accession # GSE1986) to identify genes differentially expressed in the DMT mRNA.