PITX2基因变异导致Axenfeld-Rieger综合征牙齿、上颌发育缺陷的机制研究

Axenfeld-Rieger综合征患者（有眼、牙、上颌等发育异常）可检出PITX2基因突变。PITX2调控多器官发育，但其在牙齿、上颌发育中的下游基因及调控机制尚不完全清楚。本研究拟先对Axenfeld-Rieger综合征患者筛查PITX2基因变异。再构建Pitx2诱导性基因敲除小鼠，观察牙齿、上颌发育缺陷；通过RNA测序、免疫荧光染色、染色质免疫沉淀等初步筛查牙齿、上颌发育中Pitx2下游基因；然后器官培养验证关键下游基因：先正向人为改变下游基因表达，模拟Pitx2敲除后功能障碍，重现发育缺陷；再反向改变下游基因，代偿Pitx2敲除后功能障碍，缓解发育缺陷。最后以荧光素酶报告基因实验证实检测到的突变PITX2对调控关键下游基因的影响。拟通过本研究了解PITX2基因在牙齿、上颌发育中的关键下游基因及调控机制，为针对性治疗Axenfeld-Rieger综合征、指导牙颌面组织工程提供参考。

Axenfeld-Rieger syndrome (with eye, tooth and maxilla developmental defect) has been related with PITX2 mutation. Although PITX2 regulates many organ genesis, its function in tooth and maxilla development remains unclear. In this study, the PITX2 mutation will be screened in patients with Axenfeld-Rieger syndrome, and its functional impact will be tested by luciferase assay. The inducible Pitx2 knock-out mouse will be generated to screen for Pitx2 downstream genes with RNA-seq. The target genes will be further investigated by immuno-staining and ChIP, and validated by functional tests, in which the positively- or-negatively manipulated downstream genes phenocopy or rescue the developmental defect. This study will help to identify the key mediators downstream of PITX2 in tooth and maxilla development, and facilitate targeted treatment for Axenfeld-Rieger syndrome and guided oral maxillofacial tissue engineering.