Map1b介导的Wnt5a通路调控成骨细胞分化及功能的作用机制研究

根尖周炎可引起骨质破坏，促进成骨细胞分化及骨形成是促进愈合的直接方式。成骨细胞骨架改变可影响其分化及功能，而Wnt5a是骨架调节的重要胞外信号，可促进成骨。Map1b是骨架的直接调节蛋白，推测其可能为Wnt5a调控成骨细胞的潜在靶点，但罕有研究。申请人前期研究发现Wnt5a可引起Map1b改变，而Map1b可影响成骨分化，提示Wnt5a-Map1b通路可调控成骨，但其调节机制需进一步诠释。本课题拟以构建的成骨细胞特异性敲除Wnt5a小鼠为动物模型，解析其骨表型；并以此为基础建立细胞模型，阐明Wnt5a-Map1b对成骨细胞生物学行为的影响；结合RNA-seq、Co-IP技术及挽救（Rescue）实验等剖析其具体分子调控机制；并采用小鼠疾病模型，进一步明确其临床提示作用。结果将揭示Map1b介导的Wnt5a通路在成骨细胞分化及功能中的精细调控机制，并对根尖周炎骨缺损的临床防治具有指导意义。

Periapical diseases lead to bone loss. The direct way to promote healing is to improve osteogenic differentiation and bone formation. According to the recent studies, cytoskeleton changes affected osteogenic differentiation, and Wnt5a was the important extracellular signal to regulate the dynamics of cytoskeleton, and promote bone formation as well. Map1b is the direct regulatory protein of cytoskeleton, presumably it is the potential regulatory target of Wnt5a in osteoblast, but it is still lack of direct evidence. The applicant confirmed that Wnt5a can affect Map1b, and Map1b can regulate osteogenic differentiation, suggesting Wnt5a-Map1b can regulate osteoblast differentiation, but further research still need to be performed. In this project, we intend to establish the mice model with osteoblast conditional knockout of Wnt5a（Wnt5a CKO）, and study the phenotypes; to find out the biological function and regulatory mechanism of Wnt5a-Map1b on the osteoblast differentiation and function by using RNA-seq, Co-IP technique and Rescue experiments; to explore the function of Map1b in the healing process of periapical bone loss. The results will reveal the molecular mechanism of Wnt5a-Map1b in osteogenic differentiation and bone formation, and guide the clinical strategy in the prevention and treatment of periapical bone loss in apical periodontitis.