Molecular Biology of Retinal Development

描述（由申请人提供）：本项目的长期目标是阐明脊椎动物视网膜中光感受器产生的分子调控。这些知识对于开发有效的基于干细胞的光感受器替代疗法至关重要。需要了解更多有关基因的身份，以及它们如何从其他选择中选择感光细胞的命运。在之前的资助期间的研究确定了neuroD作为感光细胞分化的重要参与者，在ngn 2->neuroD->RaxL的转录途径中。在该途径中，ngn 2在多能祖细胞中发挥作用，其下游遗传靶点包括neuroD; neuroD介导感光细胞发育程序，包括同源框基因RaxL的表达。在这个应用程序中，我们将测试的假设，感光细胞的生产采用ngn 1在ngn 2和neuroD之间的关键步骤。目的1研究ngn 1是否在正确的位置和正确的时间表达，是一个主要的基因在领导的祖细胞的光感受器path. Aim 2研究ngn 1是否明确引导祖细胞的光感受器路径，从而导致专门的光感受器生产。目的3确定ngn 1是否是感光细胞生产所必需的。目的4解决了ngn 1在感光细胞生产过程中如何与ngn 2和neuroD遗传相关。这些研究将采用分子生物学、细胞生物学、发育生物学和遗传学的一系列技术进行。该项目有望阐明调控光感受器生产的转录调控。此外，它具有临床意义。识别光感受器产生中的关键遗传因素将使体外或体内有效的光感受器产生能力，用于具有治疗目的的研究。在这个对干细胞替代疗法研究兴趣高涨的时代，这些研究是及时的。

DESCRIPTION (provided by applicant): The long-term goal of this project is to elucidate the molecular regulation of photoreceptor production in the vertebrate retina. This knowledge is imperative to the development of effective stem cell-based photoreceptor replacement therapies. Much needs to be learned about the identities of the genes involved and how they contribute to the selection of the photoreceptor fate from among the other options. Studies during the previous funding period identified neuroD as an instrumental player in photoreceptor differentiation, in a transcriptional pathway of ngn2->neuroD->RaxL. In this pathway, ngn2 functions in multipotent progenitors and its downstream genetic targets include neuroD; neuroD elicits a photoreceptor development program, including the expression of homeobox gene RaxL. In this application we will test the hypothesis that photoreceptor production employs ngn1 at a key step between ngn2 and neuroD. Aim 1 examines whether ngn1 is expressed at the right place and the right time to be a major gene in leading progenitors to the photoreceptor path. Aim 2 investigates whether ngn1 expressly steers progenitors to the photoreceptor path and, thus, leads exclusively to photoreceptor production. Aim 3 determines whether ngn1 is required for photoreceptor production. Aim 4 addresses how ngn1 genetically relates to ngn2 and neuroD during photoreceptor production. These studies will be carried out with a battery of techniques from molecular biology, cell biology, developmental biology, and genetics. This project promises to shed light on the transcriptional regulation governing photoreceptor production. Furthermore, it bears clinical implications. The identification of key genetic players in photoreceptor production will capacitate efficient in vitro or in vivo photoreceptor generation for studies with therapeutic goals. These studies are timely in this era of heightened interest in stem cell research for replacement therapies.