title: Autophagy mediates cementoblast mineralization through periostin/-catenin signaling axis under compression
design: Repair of orthodontic external root resorption and periodontal tissue dysfunction induced by mechanical force remains a clinical challenge. Cementoblasts are vital in cementum mineralization, a process important for restoring damaged cementum and regaining healthy periodontal function. Autophagy is a vital self-renewal process for cellular homeostasis under various environmental stimuli. However, how autophagy mediated cementoblast mineralization remains unclear. Here we verified that murine cementoblasts exhibit compromised mineralization under compressive force. Autophagy was indispensable for cementoblast mineralization, and autophagic activation markedly reversed the capacity for cementoblast mineralization and cementum damage in mice. Subsequently, mRNA sequencing analyses identified periostin (Postn) as a regulator of autophagy and cementoblast mineralization. Cementoblast mineralization was significantly inhibited following knockdown of Postn. Furthermore, Postn silencing downregulated Wnt transcriptional activity by promoting ubiquitination of -catenin. Together our results highlight autophagy as a mediator of cementoblast mineralization via Postn/-catenin signaling under compressive force and may provide a new strategy for the remineralization of cementum and regeneration of periodontal tissue.