GENE EXPRESSION IN AXOTOMIZED RETINAL GANGLION CELLS

视网膜神经节细胞的死亡是最终的共同途径 几乎所有的视神经疾病，包括前部缺血 视神经病变、视神经炎和压迫性视神经病变。 尽管有大量研究探讨了低氧的直接影响， 兴奋性毒素等对视网膜神经节细胞的损伤，对 这些轴突损伤细胞是大多数视神经疾病的基础， 人们对此的理解远没有那么清楚。促进神经节再生的尝试 轴突切断后细胞轴突的前提是神经节细胞胞体完整； 预防神经节细胞死亡可以期待再生吗？ 战略将会成功。因此，这项提案的总体目标是 使用最新开发的技术来更好地理解亚细胞 轴突损伤导致视网膜神经节细胞死亡的潜在事件。 工作假说是视网膜神经节细胞的轴突切断导致 启动细胞死亡程序的基因的表达，这些 可以对基因及其产物进行表征。长期目标是 调节这些基因或它们的产物，从而允许拯救 视神经损伤时的视网膜神经节细胞。 第一个具体目标是找出差异表达的基因 视网膜节细胞被切断。消减拷贝DNA(CDNA)文库 将由从轴突切除后提取的信使RNA(MRNA)制成 控制大鼠视网膜。候选的cDNA将被Northern筛选 用RNA探针进行印迹或核糖核酸酶保护试验。第二 具体目的是研究组织、物种和发育表达 识别出的基因。基因序列将被用来寻找 与其他与细胞死亡相关的基因同源。第三个具体问题 目的是表达这些基因的蛋白质产物并确定它们的 本地化和可能的功能。 这个项目与健康相关的是影响 球前和球后视神经。而这些疾病直接 损伤视神经内的轴突，不可逆转的丧失 视觉反映了视网膜内神经节细胞的死亡。 了解神经节细胞反应的亚细胞性质 轴突损伤将使这些疾病的治疗方法得以发展。这个 有机会接受正式的分子生物学培训并开展 这项研究计划还将促进申请者成为 一名独立调查员。

Death of retinal ganglion cells is the final common pathway underlying virtually all diseases of the optic nerve, including anterior ischemic optic neuropathy, optic neuritis, and compressive optic neuropathy. Despite a wealth of studies examining the direct effect of hypoxia, excitotoxins, and other injuries on retinal ganglion cells, the effect on these cells of axonal injury, which underlies most optic neuropathies, is far less clearly understood. Attempts to promote regeneration of ganglion cell axons after axotomy presupposes an intact ganglion cell soma; only by preventing ganglion cell death can it be expected that regenerative strategies will succeed. Therefore the overall goal of this proposal is to use recently developed techniques to better understand the subcellular events underlying death of retinal ganglion cells due to axonal injury. The working hypothesis is that axotomy of retinal ganglion cells causes expression of genes that turn on a program for cell death, and that these genes and their products can be characterized. The long-term goal is to modulate these genes or their products and therefore allow rescue of retinal ganglion cells when the optic nerve is injured. The first specific aim is to identify genes differentially expressed in axotomized retinal ganglion cells. A subtracted copy DNA (cDNA) library will be made from messenger RNA (mRNA) extracted from axotomized and control rat retinas. Candidate cDNAs will be screened with Northern blotting or ribonuclease protection assay using RNA probes. The second specific aim is to study the tissue, species, and developmental expression of the identified genes. Gene sequences will be used to look for homologies to other genes associated with cell death. The third specific aim is to express the protein products of the genes and determine their localization and possible function. The health-relatedness of this project is to diseases affecting the anterior and retrobulbar optic nerve. While these disorders directly damage axons contained within the optic nerve, the irreversible loss of vision reflects the death of ganglion cells contained within the retina. Understanding the subcellular nature of the ganglion cell response to axonal injury will allow development of therapies for these diseases. The opportunity to receive formal training in molecular biology and carry out this research program will also further the applicant's goal of becoming an independent investigator.