Molecular Genetics of Norma Tension Glaucoma

描述(申请人提供)：青光眼是一种常见的视神经疾病，影响着全球6000多万人，是美国失明和视力残疾的主要原因。然而，导致青光眼的生物学途径还不是很清楚，这阻碍了对这种疾病的早期发现和治疗。 因此，从分子水平上阐明青光眼的病因是非常必要的。我们鉴定了一个新的青光眼基因--TANK结合蛋白1(TBK1)，并发现该基因的重复与青光眼相关。TBK1在非眼组织中得到了广泛的研究，并在天然免疫系统中具有明确的作用。激活的TBK1刺激吞噬小体的组装和吞噬/消除细菌、蛋白质和细胞器(这一过程称为自噬)。三个自噬基因(TBK1、OPTN和TLR4)编码相互作用的蛋白质，也被描述为NTG基因。此外，在青光眼实验动物模型中，自噬与视网膜神经节细胞死亡有关。我们发现TBK1是NTG基因，为自噬在NTG的发病机制中发挥重要作用提供了进一步的证据。人类对NTG的遗传学研究和青光眼实验模型系统的数据融合提供了强有力的证据，表明自噬可能是青光眼视网膜神经节细胞死亡的一个中心过程。我们的中心假设是，在青光眼的关键病理部位，即构成视神经的视网膜神经节细胞，TBK1影响自噬。这一途径的失调(例如，通过复制TBK1)可能会启动一系列事件，导致视网膜神经节细胞凋亡、视力丧失和青光眼。我们建议使用我们独特而强大的青光眼患者队列、人类供体眼睛和具有与人类患者相同基因缺陷的转基因TBK1小鼠的集合，通过三个具体目标来验证我们的假设。我们将通过使用下一代DNA测序策略测试大量青光眼患者自噬基因的突变来识别导致青光眼的新基因。我们将确定TBK1突变(基因复制)在青光眼发展和转基因TBK1小鼠视网膜自噬激活中的作用(我们已经制作并准备进行研究)。我们还将测试刺激或阻止自噬的药物在这些小鼠中预防青光眼的能力。我们将通过识别视网膜中相互作用的蛋白质来研究TBK1缺陷导致青光眼的途径(S)。通过这些实验，我们将开始描述TBK1基因缺陷导致青光眼的生物学途径，验证青光眼的动物模型，并开始将我们的发现转化为疾病诊断和治疗的新方法。

DESCRIPTION (provided by applicant): Glaucoma is a common disease of the optic nerve that affects over 60 million people worldwide and is a leading cause of blindness and visual disability in the United States. However, the biological pathways that lead to glaucoma are not well understood, and this has hindered efforts for early detection and treatment of this condition. Consequently, there is great need to clarify the causes of glaucoma at the molecular level. We identified a new glaucoma gene, TANK binding kinase 1 (TBK1) and discovered that duplication of the TBK1 gene is associated glaucoma. TBK1 has been studied extensively in non-ocular tissues and has well- defined roles in the innate immune system. Activated TBK1 stimulates assembly of a phagosome and engulfment / elimination of bacteria, proteins, and organelles (a process known as autophagy). Three autophagy genes (TBK1, OPTN, and TLR4) encode interacting proteins and have also been described as NTG genes. Moreover, autophagy has been implicated in the retinal ganglion cell death in experimental animal models of glaucoma. Our discovery that TBK1 is an NTG gene provides additional evidence that autophagy has an important role in the pathogenesis of NTG. The convergence of data from human genetic studies of NTG and from experimental glaucoma model systems provides strong evidence that autophagy may be a central process in the pathogenesis of retinal ganglion cell death in glaucoma. Our central hypothesis is that TBK1 influences autophagy at the key site of pathology in glaucoma, the retinal ganglion cells that form the optic nerve. Dysregulation of this pathway (e.g. by duplication of TBK1) may start a cascade of events that leads to apoptosis of the retinal ganglion cells, vision loss, and glaucoma. We propose to test our hypothesis with three specific aims that use our unique and powerful collection of glaucoma patient cohorts, human donor eyes, and transgenic TBK1 mice that have the same genetic defect as human patients. We will identify new genes that cause glaucoma by testing large cohorts of glaucoma patients for mutations in autophagy genes using next generation DNA sequencing strategies. We will determine the effect of TBK1 mutation (gene duplication) on the development of glaucoma and activation of autophagy in the retina of transgenic TBK1 mice (which we have made and are ready to study). We will also test drugs that stimulate or block autophagy for their ability to prevent glaucoma in these mice. We will investigate the pathway(s) by which TBK1 defects lead to glaucoma by identifying interacting proteins in the retina. With these experiments, we will begin to characterize the biological pathway by which defects in the TBK1 gene lead to glaucoma, validate an animal model of glaucoma, and begin to translate our discoveries into new approaches to diagnosis and treatment of disease.