Single‐Cell Virtual Perturbation Screening Identifies <scp>STAT3</scp> as a Key Regulator of Dentinogenesis

Dentine formation constitutes a physiological process precisely regulated by signal transduction modules governing odontoblast differentiation and mineralisation. First, by constructing a single-cell transcriptional landscape of odontogenic tissue, we defined EFNB2+ mesenchymal cells as a primary progenitor cluster, marking the origin of the odontogenic lineage. Integrating CellRank-based fate mapping and SCENIC-based regulon specificity analysis, we identified signal transducer and activator of transcription 3 (STAT3) as a pivotal transcriptional regulator of the odontoblast lineage. Subsequently, in silico perturbations using CellOracle predicted that STAT3 ablation disrupted the developmental vector field, redirecting the fate of mesenchymal precursors away from the odontoblast lineage. To substantiate these bioinformatic predictions, functional validation using shRNA-mediated silencing and pharmacological modulation demonstrated that STAT3 was essential for the proliferation and differentiation capacity of dental mesenchymal cells. Furthermore, we generated conditional knockout mice targeting Stat3 in Osterix-expressing odontoblast progenitors, which consequently exhibited significant dentine dysplasia. Mechanistically, RNA-seq and chromatin immunoprecipitation (ChIP) assays revealed that STAT3 directly bound to the WNT2B promoter, transcriptionally activating the Wnt/β-catenin signalling pathway in dental mesenchymal cells. Overexpression of WNT2B partially rescued the odontogenic defects induced by STAT3 inactivation. This 'prediction to verification' study establishes STAT3 as a critical regulator of dentinogenesis and provides potential therapeutic targets for the treatment of dentine developmental disorders and the advancement of dentine regeneration.