MOLECULAR CONTROL OF RETINAL STEM CELL DEVELOPMENT

视网膜干细胞发育的分子控制

• 批准号: 2605218
• 负责人: Peter H Mathers
• 金额: $ 9.61万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2605218
• 关键词: cell differentiation; cell line; cell proliferation; congenital eye disorder; developmental genetics; early embryonic stage; embryonic stem cell; gene expression; gene mutation; gene targeting; homeobox genes; human genetic material tag; in situ hybridization; laboratory mouse; mammalian embryology; microphthalmos; optic tract; polymerase chain reaction; regulatory gene; retina; retinal pigment epithelium

Commitment of cells to form a retina occurs during early embryogenesis as the neural plate is regionalized into specific domains. Once specified to become retina, the precursor cells proliferate as stem cells until signaled to stop dividing and differentiate. Retinal stem cells are multipotent, giving rise to all of the cells of the pigmented and neural retina, and are capable of participating in retinal regeneration in lower vertebrates. We have chosen to study genes likely to control retinal stem cell fate in an effort to determine the molecular mechanisms that control the establishment and proliferation of the retina. Several homeobox-containing trasncriptional regulatory genes are important for the proper formation of the eye during embryonic development, including Pax6, Chx10 and Lhx2. A new family of retinal homeobox genes, Rx, is expressed in a spatial and temporal pattern consistent with a role in retinal stem cell specification and proliferation. The function of the Rx gene is crucial for proper eye formation, as overexpression causes hyperproliferation of the neural retina and retinal pigment epithelium, and targeted deletion of the Rx gene in the mouse eliminates optic vesicle formation and results in the birth of eyeless mouse pups. Our proposed studies are aimed at identifying the mechanisms by which Rx regulates early mammalian eye development. We have designed three strategies in different experimental systems to study the role of Rx during retinal formation, proliferation and differentiation. Using gene expression studies in mice carrying different ocular mutations, we will investigate whether Rx is necessary for the initial specification of retinal cell fate. An analysis of later Rx function during retinal stem cell proliferation and differentiation will be performed using molecular techniques in primary mouse retinal cultures and human retinoblastoma cells. Finally, we propose to screen DNA samples from anophthalmic patients for mutations in the human Rx gene. These experiments will elucidate the role of the Rx homeobox gene in human eye development. The proposed studies have important implications for our basic understanding of ocular organogenesis, and may contribute to medical treatment strategies for retinoblastoma, retinal degeneration and anophthalmia.

在早期胚胎发生期间发生细胞形成视网膜的承诺 随着神经板被区域性化为特定结构域。 一次 指定为视网膜，前体细胞随着茎而增殖 细胞直到发出信号以停止分裂和区分。 视网膜茎 细胞是多能的，产生了色素的所有细胞 和神经视网膜，能够参加视网膜 下脊椎动物的再生。 我们选择研究基因可能 控制视网膜干细胞命运，以确定 控制建立和增殖的分子机制 视网膜。 几个含同源词的示例调节基因是 对于胚胎期间的眼睛正确形成很重要 开发，包括PAX6，CHX10和LHX2。 一个新的视网膜家族 HONEOBOX基因Rx以空间和时间模式表示 与视网膜干细胞规范中的作用一致 增殖。 RX基因的功能对于适当的眼睛至关重要 形成，因为过表达会导致神经的过度增殖 视网膜和视网膜色素上皮，并针对Rx的删除 小鼠中的基因消除了视囊的形成，并导致 无眼鼠标的诞生。 我们提出的研究针对 确定RX调节早期哺乳动物眼的机制 发展。 我们已经在不同的实验系统中设计了三种策略 研究RX在视网膜形成，增殖和 分化。 在携带的小鼠中使用基因表达研究 不同的眼突变，我们将研究RX是否需要 用于视网膜细胞命运的初始规范。 分析 后来的Rx功能在视网膜干细胞增殖和 分子将使用一级分子技术进行分化 小鼠视网膜培养物和人视网膜细胞瘤细胞。最后，我们 建议从疾病患者中筛选DNA样品进行突变 在人类Rx基因中。这些实验将阐明 Rx Homeobox基因在人眼发育中。 拟议的研究有 对我们对眼的基本理解的重要意义 器官发生，并可能有助于治疗策略 视网膜母细胞瘤，视网膜变性和植物病。