BBS7 -SHH signaling activity regulates primary cilia for periodontal homeostasis

Purpose : This study was performed to investigate the changes in gene expression in periodontal ligament (PDL) cells between normal occlusal function and hypofunction through RNA sequencing and elucidate the related role in maintaining the PDL homeostasis. Method : Premolars extracted for orthodontic treatment were used. The teeth with occlusal contact for control group (n=17), teeth without occlusal contact for experienment group (n=17). After the PDL cells were isolated from the extracted teeth, differentially expressed gene (DEG) analysis, and real-time PCR were performed to compare the two groups. The effect of Bardet-Biedl syndrome 7 (BBS7) knockdown was evaluated by RT-qPCR, Wound healing assay, and Tubule formation assay. Result : We detected that the expression of BBS7 was downregulated in occlusal hypofunctional PDL through RNA-sequencing. Sonic Hedgehog signaling (Shh) activity was closely associated with BBS7 expression in periodontal ligament cells. In addition, the cell migration and angiogenesis were also suppressed by BBS7 knockdown in vitro. Conclusion : We suggest that BBS7 plays an essential role in maintaining Shh signaling activity for PDL homeostasis. Examination of the gene expression between normal occlusal function and hypofuntion in huMAN premolar PDL