Uncovering novel targets for retinal ganglion cell neuroprotection and axon regeneration

项目摘要 与中枢神经系统的其他神经元一样，视网膜神经节细胞（RGC）-视网膜神经节细胞的投射神经元， 视网膜损伤后不能再生。青光眼是导致失明的主要原因， 以及他们随后的死亡是导致不可逆转的视力丧失的两个关键病理事件。但没有 我们有有效的治疗方法，以防止研究资助局的脆弱性和损失。发展的一个关键障碍 新的治疗方法是我们对调节RGC存活和轴突的机制的理解不足 再生使用小鼠视神经挤压（ONC）模型，先前，我们发现去除 磷酸酶和张力蛋白同源物（PTEN）蛋白显著促进轴突再生。最近，我们 利用ONC模型，并进行了大规模的体内CRISPR筛选，以确定此类基因的关键调控因子。 机制等我们的筛选揭示了从视网膜细胞中去除促进RGC存活的多个基因 和/或轴突再生。最强的保护性表型之一属于c-Jun N- 末端激酶相互作用蛋白3（JIP 3）。然而，敲除JIP 3不仅不能促进轴突生长， 在存活的RGC中，它消除了由PTEN缺失诱导的轴突再生。在这里，我建议 在视神经损伤后的不同时间点进行有或没有JIP 3和/或PTEN的RGC的转录组学分析 神经损伤，以进一步研究JIP 3依赖性RGC存活的分子程序，和PTEN- 依赖性轴突再生此外，我将测试JIP 3在小鼠青光眼中的神经保护作用。 模型，其中眼内压升高导致RGC损失。

Project Summary Like other neurons of the central nervous system, retinal ganglion cells (RGCs)—the projection neurons of the retina—fail to regenerate after injury. In glaucoma, a leading cause of blindness, degeneration of RGC axons and their subsequent death are two key pathological events that lead to irreversible loss of vision. However, no effective treatments to prevent RGC vulnerability and loss are available. A critical obstacle toward developing novel therapeutics is our insufficient understanding of mechanisms that regulate RGC survival and axon regeneration. Using mouse optic nerve crush (ONC) model, previously, we discovered that removal of phosphatase and tensin homolog (PTEN) protein significantly promotes axon regeneration. More recently, we leveraged ONC model and undertook a large-scale in vivo CRISPR screen to identify key regulators of such mechanisms. Our screen revealed multiple genes whose removal from retinal cells promoted RGC survival and/or axon regeneration. One of the strongest protective phenotypes belonged to the knockout of the c-Jun N- terminal kinases-Interacting Protein 3 (JIP3). However, knockout of JIP3 not only fails to promote axon regeneration in survived RGCs, it abolishes axon regeneration induced by PTEN deletion. Here, I propose performing transcriptomic analysis of RGCs with or without JIP3 and/or PTEN at different time points after optic nerve injury to further investigate molecular programs underlying JIP3-dependent RGC survival, and PTEN- dependent axon regeneration. Furthermore, I will test the neuroprotective effect of JIP3 in a mouse glaucoma model in which elevation of intraocular pressure causes RGC loss.