A comprehensive RNAi based screen for genes effecting neural degeneration in C. e

描述（由申请人提供）：对影响C.神经元变性和再生在人类和其它脊椎动物模型系统中已经研究了100多年，但是我们仍然没有全面的分子模型，也没有有效的治疗方法来预防变性或诱导再生。令人惊讶的是，强大的遗传模型系统如此成功地用于研究身体模式形成，程序性细胞死亡，神经发育和许多其他重要的生物学问题，却没有被用于研究神经元变性和再生。这是因为很难设计出一种用于D。melanogaster或C.优雅最近，Hammarlund和我做了一个观察，现在有可能在C中筛选再生所需的基因。优雅我们发现，胚胎神经元缺乏？-血影蛋白正常发育（正常的生长锥运动，寻路，和目标识别），但孵化后经历运动诱导的轴突切断，然后再生。这是一种强健的表型，在动物成年之前，每只动物中的大多数连合轴突断裂并再生。随着每个轴突切断和再生周期的发生，再生逐渐失败，因此成年人显示出严重异常的神经系统。这种良好表征的再生表型在C。elegans模仿哺乳动物神经元响应轴突切断的表型。本研究拟利用RNAi敲除技术来检测蠕虫基因组中各个基因在神经元变性和再生过程中的功能。最近，发现了两种使神经元对RNAi敏感的基因突变。这种致敏的遗传背景已被用于并验证在突触传递中起作用的基因的成功的大规模RNAi筛选。有充分的理由相信，这种技术可以用于筛选基因，功能退化和再生使用的<$-血影蛋白突变体表型作为基础的分析。如果成功的话，这将是第一个无偏见的“遗传”筛选在神经元变性和再生中起作用的基因，并将确定新的基因作为靶向神经元变性和再生的治疗方法的切入点。这一建议代表了第一个无偏见的“遗传”筛选基因功能的神经元变性和再生在C。优雅如果成功的话，它将确定新的基因作为治疗的切入点，旨在预防神经元变性和诱导神经元再生。

DESCRIPTION (provided by applicant): A comprehensive RNAi screen for genes effecting neuron degeneration and regeneration in C. elegans Neuronal degeneration and regeneration has been studied in humans and other vertebrate model systems for over 100 years and yet we still do not have a comprehensive molecular model nor an effective treatment to prevent degeneration or induce regeneration. Surprisingly, the powerful genetic model systems used so successfully to study body pattern formation, programmed cell death, neural development and many other important biological problems have not been used to study neuronal degeneration and regeneration. This is because it has been difficult to devise a robust screening assay for neural regeneration in either D. melanogaster or C. elegans. Recently, Hammarlund and myself made an observation that now makes it possible to screen for genes required for regeneration in C. elegans. We discovered that embryonic neurons lacking ¿-spectrin develop normally (normal growth cone motility, pathfinding, and target recognition), but after hatching undergo a movement-induced axotomy followed by regeneration. This is a robust phenotype, with most commissural axons in each animal breaking and regenerating before the animal reaches adulthood. There is a progressive failure of regeneration as each cycle of axotomy and regeneration takes place so that the adult displays a severely abnormal nervous system. This well-characterized regeneration phenotype in C. elegans mimics the phenotype of mammalian neurons in response to axotomy. I propose to use RNAi knockdown to assay the function of every gene in the worm genome in the process of neuronal degeneration and regeneration. Recently, two genetic mutations were identified that sensitize neurons to RNAi. This sensitized genetic background has been used and validated in a successful large scale RNAi screen for genes that function in synaptic transmission. There is every reason to believe that this technique can be used to screen for genes that function in degeneration and regeneration using the ¿-spectrin mutant phenotype as the basis for the assay. If successful, it would be the first unbiased "genetic" screen for genes functioning in neuron degeneration and regeneration and should identify novel genes as entry points for theurapies targeting neuronal degeneration and regeneration. This proposal represents the first unbiased "genetic" screen for genes functioning in neuron degeneration and regeneration in C. elegans. If successful it will identify novel genes as entry points for therapies aimed at the prevention neuronal degeneration and the induction of neuronal regeneration.