双光子激光建立斑马鱼脊髓损伤模型及sema4e/plxnd1在斑马鱼脊髓损伤后再生中的作用机制

Due to the amazing regenerative capacity, zebrafish has become an ideal model for studying the regeneration of spinal cord injury. The multiphoton laser has the advantages of quantification and accurate orientation for tissue injury. In this proposal, we will use multiphoton laser to establish the model for spinal cord injury in zebrafish, track the whole process of regeneration after spinal cord injury, with living image. Injury model of zebrafish is good to investigate the function of specific genes in the regeneration. Axon guidance molecules, for example, sema family, play key roles in neurogenesis and angiogenensis. In our previous study, sema4e and plxnd1 were upregulated in the neuroregeneration post spinal cord injury, further, sema4e and plxnd1 shown the similar expression patterns after spinal cord injury, taken all previous data together, we asked: whether plxnd1 is the receptor of sema4e? Whether the roles of sema4e in neurogenesis and angiogenesis are mediated by its receptor plxnd1? We will elucidate the roles of sema4e/plxnd1 on regeneration after spinal cord injury, with the detail studies on molecules, cells, tissues and animals. This proposal will establish a new model for spinal cord injury on zebrafish, show the living image for regeneration. We will also possibly find a new pair of ligand-receptor in axon guidance molecules. If the proposal get funded, our work will provide important technical support and theory basis for plenty of studies on repairment of nerve and blood vessle injuries.

斑马鱼因其具有独特的脊髓损伤后能自主修复的能力而成为研究脊髓损伤的重要模型。双光子激光可对组织进行定位定量损伤。我们将首次探索运用双光子激光建立斑马鱼脊髓损伤模型，并进行活体连续跟踪成像显示损伤后修复全过程。斑马鱼脊髓损伤模型还可用于研究修复相关基因的功能和机制。轴突导向分子如sema家族在神经和血管生成中起到了非常关键的作用。我们前期结果显示，sema4e及plxnd1在斑马鱼脊髓损伤后都显著上调，提示这对基因在促进修复中可能发挥协同作用，而它们高度密切的表达关系提示我们：sema4e的受体是否是plxnd1？后者是否介导了前者对脊髓损伤后的神经和血管修复？我们将从分子、细胞、组织、整体动物等不同层次研究它们对斑马鱼脊髓损伤修复的作用。本项目将建立一种新的定位定量脊髓损伤模型及活体成像显示脊髓再生全过程，更可能发现一对新的轴突导向分子的配-受体，为众多损伤修复研究提供技术支持和理论基础。

脊髓损伤是一种导致感觉和运动功能严重致残的神经性疾病。如何帮助神经元再生是一个重要的临床相关课题。斑马鱼具有哺乳动物所不具备的神奇的神经损伤后再生能力，为神经再生的机制研究提供了理想的动物模型。在本基金的资助下，我们利用斑马鱼成鱼和幼鱼脊髓损伤模型，探讨了在脊髓损伤后的再生过程中那些能够帮助神经元再生的分子。在我们的工作中，不但建立了双光子激光损伤幼年斑马鱼脊髓的模型，而且发现contactin 2, MVP, HMGB1等分子在斑马鱼神经再生中起到了关键的作用。我们的这些研究为脊髓损伤的临床治疗提供了坚实的实验数据和理论基础。本项目共发表4篇SCI 论文，培养2名研究生。