Femtosecond laser axotomy for in vivo nerve regeneration studies in C elegans

描述(申请人提供)：脊髓损伤并导致瘫痪，在美国影响超过25万人，在全球影响数百万人。阻止轴突再生发生在中枢神经系统(CMS)的生物学原因仍然难以捉摸。在简单的遗传模型生物中，缺乏适合于解决这些问题的实验技术，推迟了这一领域的发现步伐。最近，我们已经证明，激光手术可以作为一种精确的切割工具来切割线虫线虫中严重的单个神经元。在手术动物中，切断的轴突自发再生，神经和行为功能完全恢复。我们的第一个目标是非常详细地研究飞秒激光消融组织的特性，并控制其切割线虫内轴突的精度，同时最大限度地减少对再生过程的干扰。这项建议的主要目标是了解调节轴突再生的分子机制和事件。我们的具体建议如下：1.确定激光手术对组织的损伤程度，并为大规模筛查设置最佳条件。2.描述和了解切断轴突两侧膜上发生的动态事件。3.发现再生过程发生所必需的基因和条件。在美国和世界上，每年有数十万人受到神经损伤或内部创伤造成的并存疾病的影响。中枢神经系统神经再生能力不足是患者康复差的主要原因。这项提案中提出的研究将为神经再生这一引人入胜的过程提供新的见解，并有望为治疗提供新的途径。

DESCRIPTION (provided by applicant): Spinal cord injuries with consequent paralysis affect more than 250,000 people in the US and several million worldwide. The biological causes that prevent axonal regeneration to occur in the central nervous system (CMS) are still elusive. The lack of experimental techniques suited to address these questions in simple genetic model organisms has delayed the pace of the discoveries in this field. Recently, we have demonstrated that laser surgery can be used as a precise cutting tool to severe individual neurons in the nematode Caenorhabditis elegans. In the operated animals, the cut axons spontaneously regenerated with a complete recovery of the neuronal and behavioral function. Our first goal is to investigate in great detail the properties of femtosecond laser ablation of tissue and control its precision for severing axons inside C. elegans with minimal interference to the regeneration processes. The broad goal of this proposal is to understand the molecular mechanisms and the events that regulate axonal regeneration. We propose specifically to proceed as follow: 1. Determine the extent of tissue damage caused by the laser surgery and set optimal conditions for large scale screens. 2. Characterize and understand the dynamic events happening on the membrane at both sides of the severed axon. 3. Discover the genes and conditions that are essential for the regeneration process to occur. Hundred of thousands of people each year in the US and in the world are affected by paralisys caused by injuries or internal traumas of the nerves. The lacking ability of nerves in the Central Nervous System to regenerate is the main reason of the minimal recovery of the patients. The studies presented in this proposal will provide new insights into the fascinating process of nerve regeneration and hopefully offer new avenues for therapies.