增加神经元突起分支数量是脊髓损伤修复的关键，而细胞骨架重排是突起分支形成的必要条件。Rho信号通路是调节细胞骨架运动的主要信号通路, spastin作为一种微管切割蛋白，目前尚不清楚spastin参与Rho信号通路在突起分支和脊髓损伤修复中的作用。我们的研究结果表明，spastin能够与Rho信号通路的下游蛋白CRMP5相互作用并介导微管调控神经元的发育；另外，高通量测序和蛋白组学发现，spastin能与Rho信号通路的下游的多个蛋白发生相互作用。据此，我们提出科学假设：Spastin参与Rho信号通路调控神经突起侧枝形成。本项目拟通过形态学、分子生物学、电生理学等技术，从体外细胞培养和体内动物模型获得spastin参与Rho信号通路调控神经突起侧枝形成的证据，阐明spastin参与该通路促进神经元分支形成的作用机制，为确立spastin作为脊髓损伤治疗的新靶点提供更充分的科学依据。

Increasing the number of neurite branches is the key to the repair of spinal cord injury, and the rearrangement of cytoskeleton is essential for the formation of neurite branches. Rho signaling pathway is the main signal regulating cytoskeleton movement. It is not clear that spastin, a microtubule cleaving protein, is involved in Rho signaling pathway in the neurite branch and repair of spinal cord injury. Our previous studies have shown that spastin interacts with CRMP5, a downstream protein in the Rho signaling pathway, and it mediates microtubule movement in the regulation of neurite development. In addition, we found spastin interacts with several downstream proteins of the Rho signaling pathway by high-throughput sequencing and proteomics. Therefore, we propose a scientific hypothesis that spastin is involved in the regulation of Rho signaling pathway in the formation of neurite lateral branches. By morphological, molecular biological and physiological approaches, in neuronal cultures in vitro and in SCI rat model in vivo, the project aims to obtain the evidences that spastin is involved in the regulation of neurite outgrowth by Rho signaling pathway, to elucidate the mechanism of spastin promoting neuronal branching in Rho signaling pathway, and to provide a scientific basis for the establishment of spastin as a new target for the treatment of spinal cord injury.