VISUAL SYSTEM DEVELOPMENT AND SYNAPTOGENESIS

利用我们的专家解剖知识的苍蝇的视叶，我们将研究基因的表达和功能在果蝇感光末梢和他们的目标internouron在第一个神经桩，椎板。我们的长期目标是了解多接触突触（二分体、三分体等）的功能组织，它们的形成以及神经活动在这一过程中的作用。目前的目标是研究感光末梢及其中间神经元中的突触组织，以及编码突触蛋白的基因的功能作用，特别是通过表型分析和椎板中基因表达模式所定义的。使用先进的共聚焦，定量EM，serial-em，免疫EM和E-D重建方法，并由熟练的人员来实现这些，我们将精确地测定对照和突触突变果蝇的表型。我们将研究：A。突触蛋白基因在感光末梢的功能作用，从突变体的EM表型，如米尔顿，noC，amphiphysin，cspa和D-亨廷顿蛋白，和新的突变体的屏幕正在进行合作实验室的全眼马赛克苍蝇与ERG的缺陷，是由于受损的传输层。 基因产物在光感受器末梢中的体内和体外表达，使用针对光感受器末梢处的突触前位点及其突触后靶细胞层的探针，用去卷积共聚焦图像可视化并通过免疫EM定位。C.视觉突触的结构组织和基因表达的动态方面，以及神经活动在传入光感受器四分体及其反馈伙伴的发育组装中的作用，以及成年果蝇在光诱发活动后的短期突触发生。D.在第二神经桩，或髓质，由长感光轴突和板层细胞终端支配的远端struita的微电路，使用有针对性的表达的EM标记物在髓质细胞，提供一个基础上，解释在这个复杂的神经桩突变结构。这里提出的研究，因为他们的目的是产生一个基本的模型适用于多接触突触，如二分体和三分体广泛发现在视觉系统中，将有助于在疾病状态的扰动的知识，视觉突触在其生长，发育和功能，以及这些的遗传基础。

Exploiting our expert anatomical knowledge of the fly's optic lobe, we will examine the expression and function of genes in Drosophila photoreceptor terminals and their target internourons in the first neuropile, the lamina. Our long-term objective, for which fly photorecepto tetrad synapses Are a genetically manipulable model, is to understand the functional organization of multiple-contact synapses (dyads, triads, etc.), their formation and the role of neural activity in this process. Current objectives are to study synaptic organization in photoreceptor terminals and their interneurons, and the functional role of genes that code for synaptic proteins, especially as defined by phenotypic analyses of, and patterns of gene expression in, the lamina. Using advanced confocal, quantitative-EM, serial-em, immuno-EM and E-D reconstruction methods, and skilled personnel to implement these, we will precisely assay the phenotypes of control and synaptic mutant flies. We will examine: A. The functional role of genes for synaptic proteins in photoreceptor terminals, from EM phenotypes of mutants such as milton, noC, amphiphysin, cspa and D-huntingtin, and of new mutants from screens being conducted in collaborating laboratories for whole-eye mosaic flies with ERG defects that are attributable to impaired transmission in the lamina. The in vivo and in vitro expression of gene products in photoreceptor terminals, using probes directed to the pre-synaptic site at the photoreceptor terminal and to its lamina post- synaptic target cells, visualized with deconvolved confocal images and localized by immuno-EM. C. Dynamic aspects of structural organization and gene expression at visual synapses, and the role of neural activity in both the development assembly of afferent photoreceptor tetrads and their feedback partners, and short-term synaptogenesis in adult flies after light-evoked activity. D. The micro-circuits of distal straita in the second neuropile, or medulla, innervated by long photoreceptor axon and lamina cell terminals, using targeted expression of EM markers in medulla cells, to provide a basis upon which to interpret mutant structure in this complex neuropile. The studies proposed here, because they aim to produce a basic model of synaptogenesis applicable to multiple-contact synapses, such as the dyads and triads found widely in visual systems, will contribute to knowledge of the perturbations in disease states to which visual synapses are susceptible during their growth, development and function, and to the genetic bases of these.