NEW NEURONS IN THE RETINA

该项目的长期目标是确定 细胞相互作用在调节神经元承诺和 硬骨神经发育和再生过程中的分化 视网膜，特别强调光感受器。《纽约时报》的新焦点 研究计划是关于特殊的细胞-细胞连接作为 感应信号事件。下一个项目的具体目标 期间为： I.表征基因的表达和发育调节 用电子显微镜和扫描电子显微镜观察硬骨视网膜中钙粘附素/黏附连接 免疫细胞化学分析。 II.研制针对硬骨N-钙粘附素的单特异性抗体和核探针 利用斑马鱼N-钙粘蛋白基因克隆和测序 斑马鱼R-钙粘附素的cDNA，并产生合成肽和融合 产生抗体以阻断钙粘附素介导的细胞-细胞的蛋白质 粘附力。 III.检验顶端连接复合体相关的假设 与锥体而不是杆状感光细胞表型有关 检测细胞钙粘蛋白mRNA和蛋白的表达谱 视锥分化的开始，在视杆前体和分化视杆上， 以及在成年鱼中引起手杖再生的损伤。 IV.检验钙粘附素/黏附连接介导选择的假说 光感受器在体外模型系统中的命运(整体器官培养 胚胎/幼鱼眼睛)。阻断N-和R-钙粘蛋白介导的细胞-细胞 与抗体、融合蛋白、N端片段的粘附性 分子，或含有特定结合序列的合成肽 或间接通过低钙、钙通道拮抗剂，以及 磷酸酪氨酸磷酸酶抑制剂钒酸。监控生产 具有杆状和锥体特异性单抗的光感受器和 同型特异性视蛋白探针原位杂交。 这里概述的研究旨在揭示涉及到 光感受器的发育与再生替代 鱼视网膜中的光感受器，可能有助于更好地了解 视网膜细胞定位的重要细胞和分子因素 和差异化。这些信息可以提供对 受损视网膜组织的替代疗法。

The long range objectives of this project are to determine the role of cellular interactions in regulating neuronal commitment and differentiation during development and regeneration of the teleost neural retina, with special emphasis on photoreceptors. The new focus of the research plan is on specialized cell-cell junctions as mediators of inductive signalling events. The specific goals for the next project period are: I. Characterize the expression and developmental regulation of cadherins/adherens junctions in teleost retina by electron microsopic and immunocytochemical analyses. II. Develop monospecific antibodies and riboprobes for teleost N-cadherin and R-cadherin by using zebrafish N-cadherin cDNA to clone and sequence cDNAs for zebrafish R-cadherin, and produce synthetic peptides and fusion proteins for generating antibodies that block cadherin-mediated cell-cell adhesion. III. Test the hypothesis that apical junctional complexes are associated with commitment to the cone but not the rod photoreceptor phenotype by examining the profile of expression of cadherin mRNA and protein at the onset of cone differentiation, on rod precursors and differentiating rods, and following lesions that induce regeneration of canes in adult fish. IV. Test the hypothesis that cadherins/adherens junctions mediate choice of photoreceptor fate in an in vitro model system (organ culture of whole embryonic/larval fish eyes). Block N- and R-cadherin-mediated cell-cell adhesion with antibodies, fusion proteins, N-terminal fragments of the molecules, or synthetic peptides containing the specific binding sequence HAV, or indirectly by low Ca+ +, calcium channel antagonists, and the phosphotyrosine phosphatase inhibitor vanadate. Monitor production of photoreceptors with rod-and cone-specific monoclonal antibodies and with in situ hybridization with isotype-specific opsin probes. The studies outlined here, designed to uncover mechanisms involved in photoreceptor development and the regenerative replacement of photoreceptors in the fish retina, may lead to a better understanding of the cellular and molecular factors important for retinal cell commitment and differentiation. This information could provide insights into replacement therapies for damaged retinal tissue.