Genomics of Mouse Molar Tooth Development
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Date
2025
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Publisher
Saudi Digital Library
Abstract
Odontogenesis is consistent with the sequential morphological stages observed in
mammalian organogenesis, making it an excellent system to study the organogenesis processes.
Using RNA-seq, this study analysed transcriptomic dynamics during critical stages of mouse molar
development (bud, cap, and bell), where data were collected from wild-type mouse embryos at
embryonic days, and identified both substantial temporal changes in gene expression reflecting
important morphogenetic transitions as well as the occurrence of cellular differentiation processes.
Using the Galaxy platform, the study found extensive regulation of genes between developmental
stages, suggesting complex spatiotemporal control. Gene expression changes between bud and bell
were more pronounced than between transitions involving an intermediate leaf phenotype. Similar
transcriptional changes were highlighted in their intensity and directionality by DESeq2-generated
volcano plots and MA plots using Galaxy software, indicating that dynamic cellular activity occurs
within developing tooth germs.
Representative transcription factors and signalling pathways such as Wnt, BMP, FGF and
SHH were found to be highly enriched, supporting their previously established regulatory roles in
tooth morphogenesis. STRING-based protein interaction networks further defined the functional
gene modules that are key to appropriate progression through development. The analysis identified
key nodes, including Pitx2, Lef1 and Wnt10a, which are consistent with known roles in
odontogenesis. Comparisons with existing literature confirmed patterns of gene expression,
particularly relevant to previously published single-cell RNA-seq studies, indicating epithelial
cell-type specificity and mesenchymal interactions during tooth formation. These findings reaffirm
the importance of transcriptional dynamics in the temporal context of enamel knot formation and
cusp patterning, which are essential to proper molar morphology. This study makes a significant
contribution to the understanding of the molecular basis of tooth morphogenesis and
organogenesis. These findings may have future applications to the treatment of developmental
genetic disorders of teeth, regenerative dentistry, and evolutionary biology. Additional studies with
single-cell resolution, proteomic verification, and high-throughput functional experiments are
suggested to confirm these regulatory networks and provide more mechanistic details.
Description
Keywords
Odontogenesis, RNA-seq, Differential Gene Expression, Molar Development, Transcription Factors, Signalling Pathways, Tooth Morphogenesis, Galaxy Bioinformatics
Citation
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