Transcriptional Regulation of Retinal Development

首席调查员/项目主任(最后、第一、中间)：项梦清 研究及相关其他项目信息 1.*是否涉及人类受试者？是，不是 1.a.如果是，对人类受试者 IRB的审查正在进行中吗？是，不是 IRB批准日期： 豁免编号：1 2 3 4 5 6 人类主题保证编号 2.*是否使用脊椎动物？是，不是 2.a.如果是，脊椎动物 IACUC的审查正在进行中吗？是，不是 IACUC批准日期：07-28-2006 动物福利保障编号A3328 3.*是否为专有/特权信息是否 是否包含在应用程序中？ 4.a.*此项目是否对Yes No有实际或潜在影响 环境？ 4.B.如果是，请解释： 4.C.如果该项目对环境有实际或潜在的影响，是否已批准豁免或环境评估(EA)或 是否执行了环境影响报告书(EIS)？是，不是 4.D.如果是，请解释： 5.a.*此项目是否涉及美国以外的活动或是否 与国际合作者建立伙伴关系？ 5.B.如果是，请列出以下国家/地区： 5.c.可选解释： 6.*项目摘要/摘要3641-项目_概要.pdf模拟类型：应用程序/pdf 7.*项目说明8884-Project_Relationance.pdf模拟类型：应用程序/pdf 8.参考书目和参考文献7570-Reference.pdf参考文献类型：应用程序/pdf 9.设施和其他资源1861-Facilities.pdf Mime类型：应用程序/pdf 10.Equipment 8804-Equipment.pdf模拟类型：应用/pdf 追踪编号：其他信息第5页OMB编号：4040-0001 到期日：04/30/2008 首席调查员/项目主任(最后、第一、中间)：项梦清 项目总结：该提案的长期目标是了解导致 不同类型视网膜细胞的测定、分化和维持。在哺乳动物 视网膜发生，七类细胞由多能祖细胞通过各种内源性细胞的作用而指定。 和外在因素。涉及功能丧失和功能获得的分子遗传学研究进展 一些方法已经发现了一些转录因子作为视网膜发生的关键内在调节因子。 这些因素被发现在不同的发育过程中作用于建立祖细胞多能性， 定义祖细胞能力，决定细胞命运，和/或指定细胞类型和子类型。因此， 在视网膜形成过程中，转录因子在控制细胞决定和分化过程中起着关键作用。 尽管有这些重要的进展，然而，下游的分子靶标和信号事件 许多参与视网膜发育的转录因子仍然知之甚少。 在这一应用中，提出了将专注于分子和发育事件的实验 视网膜神经节细胞(RGC)的关键调控因子Brn3b POU结构域转录因子调控 分化和生存及其下游分子。将追求四个具体目标：i) 了解Brn3b是视网膜细胞分化的负调控因子。利用分子、细胞和 过度表达的方法，拟议的研究旨在验证在Brn3b-/-视网膜中作为多个 参与非RGC细胞发育的基因，证实Brn3b对非RGC细胞的抑制作用 分化，并确定介导其抑制效应的下游基因；ii)研究 过度表达分析视网膜发育过程中的EBF因子。我们的目标是使用一种过度表达 研究EBF因子及其显性-负性形式或其击倒作用的方法 视网膜细胞分化与RGC轴突发现；III)研究EBF因子的生物学功能 在视网膜发育过程中使用靶向突变体。目标是使用有针对性的EBF小鼠突变体 补充过度表达研究以揭示EBF因子的作用并建立功能 它们与Brn3b在哺乳动物视网膜发生中的关系；以及iv)分析CXCR4的作用 在视网膜发育过程中。在这一目标中，将使用功能损失和功能增益两种方法 明确CXCL12-CXCR4趋化因子信号通路在小鼠视网膜细胞分化和分化中的作用 RGC轴突投射，并探索Brn3b介导的下游信号事件。建议进行的研究 共同为视网膜细胞所涉及的基因调控网络提供了重要的见解 多元化和差异化。 项目说明第6页

Principal Investigator/Program Director (Last, first, middle): Xiang, Mengqing RESEARCH & RELATED Other Project Information 1. * Are Human Subjects Involved? Yes No 1.a. If YES to Human Subjects Is the IRB review Pending? Yes No IRB Approval Date: Exemption Number: 1 2 3 4 5 6 Human Subject Assurance Number 2. * Are Vertebrate Animals Used? Yes No 2.a. If YES to Vertebrate Animals Is the IACUC review Pending? Yes No IACUC Approval Date: 07-28-2006 Animal Welfare Assurance Number A3328 3. * Is proprietary/privileged information Yes No included in the application? 4.a. * Does this project have an actual or potential impact on Yes No the environment? 4.b. If yes, please explain: 4.c. If this project has an actual or potential impact on the environment, has an exemption been authorized or an environmental assessment (EA) or environmental impact statement (EIS) been performed? Yes No 4.d. If yes, please explain: 5.a. * Does this project involve activities outside the U.S. or Yes No partnership with International Collaborators? 5.b. If yes, identify countries: 5.c. Optional Explanation: 6. * Project Summary/Abstract 3641-Project_summary.pdf Mime Type: application/pdf 7. * Project Narrative 8884-Project_relevance.pdf Mime Type: application/pdf 8. Bibliography & References Cited 7570-Reference.pdf Mime Type: application/pdf 9. Facilities & Other Resources 1861-Facilities.pdf Mime Type: application/pdf 10. Equipment 8804-Equipment.pdf Mime Type: application/pdf Tracking Number: Other Information Page 5 OMB Number: 4040-0001 Expiration Date: 04/30/2008 Principal Investigator/Program Director (Last, first, middle): Xiang, Mengqing Project Summary: The long-term objective of this proposal is to understand the molecular events that lead to the determination, differentiation and maintenance of different retinal cell types. During mammalian retinogenesis, seven classes of cells are specified from multipotent progenitors by the action of various intrinsic and extrinsic factors. Recent molecular genetic studies involving loss-of-function and gain-of-function approaches have uncovered a number of transcription factors as pivotal intrinsic regulators of retinogenesis. These factors are found to act at different developmental processes to establish progenitor multipotency, define progenitor competence, determine cell fates, and/or specify cell types and subtypes. Therefore, transcription factors play key roles in controlling cell determination and differentiation during retinogenesis. Despite these important advances, however, the molecular targets and signaling events downstream from many transcription factors involved in retinal development still remain poorly understood. In this application, experiments are proposed that will focus on the molecular and developmental events controlled by the Brn3b POU domain transcription factor, a crucial regulator of retinal ganglion cell (RGC) differentiation and survival, and its downstream molecules. Four specific aims will be pursued: i) to understand Brn3b as a negative regulator of retinal cell differentiation. Utilizing molecular, cellular and overexpression approaches, the proposed studies aim to verify in Brn3b-/- retinas the upregulation of multiple genes involved in non-RGC cell development, confirm the inhibitory effect of Brn3b on non-RGC cell differentiation, and identify downstream genes that mediate its repressive effects; ii) to investigate the role of Ebf factors during retinal development by overexpression analysis. We aim to employ an overexpression approach to investigate the effect of Ebf factors and their dominant-negative forms or their knockdown on retinal cell differentiation and RGC axon pathfinding; iii) to study the biological function of Ebf factors during retinal development using targeted mutants. The goal is to use targeted Ebf mouse mutants to complement the overexpression studies to uncover the role of Ebf factors and establish a functional relationship between them and Brn3b during mammalian retinogenesis; and iv) to analyze the role of Cxcr4 during retinal development. Both loss-of-function and gain-of-function approaches will be used in this aim to define the role of the Cxcl12-Cxcr4 chemokine signaling pathway during mouse retinal cell specification and RGC axon projection and to explore Brn3b-mediated downstream signaling events. The proposed studies together are expected to provide important insights into the genetic regulatory networks involved in retinal cell diversification and differentiation. Project Description Page 6