Notch signaling controls periodontal ligament maturation through regulating Lamin A

Tooth eruption is a continuous biological proces with dynamic changes at cellular and tissue levels particularly within the periodontal ligament (PDL). Occlusion completion is a significant physiological landmark of dentintion establishment. However the implication and molecular networks engaging in of this event on the the final PDL maturation are still largely unknown. In this study, using rat and mouse molar teeth and transgenic approaches, as well as a human PDL cell line by combining RNAseq and proteomic analysis systematically, we screened the key molecular links in regulating PDL maturation before and after occlusion establishiment. We discovered Notch, a key molecular pathway in regulating stem cell fate and differentiation, is a major player in the event. Intercepting Notch pathway by deleting its key canonical transtripitonal factor: RBP-Jkappa using conditional knocking out strategy in the mice delayed PDL maturation. We also identified that Lamin A, a cell nuclear lamina member, is one unique marker of PDL maturation and its expression is under the control of Notch signalling. Our study therefore provides a deep insight of how PDL maturation is regulated molecularly and we expect the outcomes to be applied to better understand the molecular regulation networks and physiological conditions such as tooth eruption and movement, and also for periodontal diseases. Overall design: Comparison of PDL expression upon occlusal contact establishment (occurs between P18 and P28).