破骨细胞骨架的高度重组和介导作用是细胞迁移、极化和膜泡运输的基础，决定着其骨吸收功能，Rho GTPases家族是其主要的调节因子。申请者发现，在破骨细胞骨吸收过程中细胞骨架发生剧烈改变，并伴随Rho GTPases转录水平的规律性变化，但Rho GTPases在骨吸收中的作用机制尚未明确。本项目首先通过M-CSF和RANKL诱导小鼠骨髓细胞产生成熟的破骨细胞，然后利用Rho GTPases慢病毒过表达或干扰载体转染此细胞，采用扫描电镜和Western blot检测对其骨吸收的影响，筛选出影响骨吸收的Rho GTPases。在此基础上，采用电镜、超分辨率激光共聚焦显微镜、Western blot等研究其对细胞骨架的影响及对破骨细胞迁移、极化和膜泡运输中关键蛋白的表达和分布的调控，揭示Rho GTPases家族通过调控细胞骨架，进而影响破骨细胞骨吸收功能的分子机理。

The recombination and mediation of cytoskeleton is the base of osteoclast polarization, migration and vesicular transport, it plays decisive role of the bone resorption. Rho GTPases family is a major regulator of cytoskeletal. Applicants finds that cytoskeleton changes drastically during cell maturation and bone resorption, accompanying with regular variation of Rho GTPases. However, the role of Rho GTPases in this process has not yet been defined explicitly. The mature osteoclasts are induced from the mouse bone marrow cells by M-CSF and RANKL, and then it makes use of the lentiviral vector overexpression or interference vector transfection cells. Through scanning electron microscope and Western blot, we filter the Rho GTPases which affecting bone resorption. On this basis, the project detects the changes of the key protein expression and distribution in the influence on osteoclasts cytoskeleton, migration, polarization,vesicular trafficking by electron microscope, Ultra-high resolution laser scanning confocal microscopy, Western blot etc. This project will illuminate its molecular mechanism by reveling the fact that Rho GTPases regulate the cytoskeleton to affect the process of osteoclasts migration, polarization and vesicular trafficking.