Genetic Analysis of Synaptic Function

描述（由申请人提供）：神经元之间的有效和稳定的信息传递发生在专门的细胞-细胞接触部位，称为突触，但它们的结构和强度都不是静态的。突触被重新排列，因为神经元回路在整个生命过程中随着神经元活动的变化而得到改善。这个过程通常被认为是学习和记忆的基础。突触强度和/或布线的失败或甚至细微变化可干扰神经元回路并引起神经、精神和/或神经退行性疾病。然而，尽管取得了相当大的进展，许多控制突触功能的分子机制仍然知之甚少或未知。使用模型系统果蝇，我们采用了正向遗传方法，并确定了大量的候选基因，可能表达关键和新的突触组件。现在的主要问题是：（1）哪些基因发生了突变，（2）神经元内的潜在蛋白质在哪里？这项研究旨在回答我们新发现的4种突变的问题，这些突变都影响突触传递的基本突触前机制。所获得的知识（突变蛋白的分子身份和定位及其对突触功能的意义）以及新产生的工具（转基因和抗体）将为成功获得大规模联邦资助以剖析突触功能背后的突变分子机制提供必要的基础。具体地，目标1将物理地鉴定由突触突变B332、B689、B773和B 936突变的基因座。这将通过将突变遗传映射到少数基因来实现，然后将允许对突变进行分子鉴定并将突变与特定基因相关联。目的2将解决新鉴定的蛋白质的组织特异性和亚细胞定位。提出的识别和随后的功能分析的新组件控制突触的结构和/或功能，将不仅推进我们的基本生物化学知识，但也可能产生关键的见解同源蛋白质在人类的病理学和加速发展的新概念，用于检测，治疗和/或预防神经和精神疾病。

DESCRIPTION (provided by applicant): The efficient and stable transfer of information among neurons occurs at specialized cell-cell contact sites, called synapses but neither their structure nor their strength is static. Synapses are rearranged as neuronal circuitry is refined upon changes in neuronal activity throughout life. This process is generally believed to underlie learning and memory. Failure or even subtle changes in synaptic strength and/or wiring can disturb neuronal circuits and cause neurological, psychiatric, and/or neurodegenerative disorders. However, despite considerable progress, many molecular mechanisms that govern synaptic function are still poorly understood or not known. Using the model system Drosophila, we employed a forward genetic approach and identified a large number of gene candidates that may express critical and novel synaptic components. The major questions are now: (1) Which genes have been mutated and (2) where are the underlying proteins localized within a neuron? The proposed study is designed to answer these questions for 4 of our newly identified mutations, which all affect essential presynaptic mechanisms of synaptic transmission. The gained knowledge (molecular identity and localization of the mutated proteins and their significance for synaptic function) together with the newly produced tools (transgenes and antibodies) will then provide an essential foundation to successfully obtain large-scale federal funding to dissect the mutated molecular mechanisms underlying synaptic function. Specifically, Aim 1 will physically identify the gene locus that is mutated by the synaptic mutations B332, B689, B773, and B936. This will be achieved by genetically mapping the mutation to a small number of genes, which will then allow a molecular identification of the mutation and an association of the mutation with a particular gene. Aim 2 will resolve the tissue-specific and subcellular localization of the newly identified proteins. The proposed identification and subsequent functional analysis of new components governing synaptic structure and/or function will not only advance our basic biochemical knowledge but may also yield critical insights into the pathologies of homologous proteins in human and accelerate the development of new concepts for detecting, treating, and/or preventing neurological and psychiatric disorders.