Role of 14-3-3epsilon in neurite initiation

项目摘要/摘要 大脑中复杂的神经元网络的形成需要精确的神经发生和神经元 在发育过程中，伴随着轴突和棘突的形成而迁移。如果轴突和脊椎的形成 如果受到干扰，它会导致一系列疾病，如精神疾病。最近，患有老年痴呆症的患者 已经报道了17p13.3染色体区域的微复制以及表现出 这种综合征一直在增加。有趣的是，患有这种17p13.3微重复综合征的患者 表现出严重的神经和形态缺陷，包括癫痫、智力低下和自闭症 谱系障碍(ASD)。更有趣的是，分析这种新的人类遗传综合症的研究阐明了 大约70kb的关键区域与ASD密切相关，并且该区域包含单个 该基因编码14-3-3ε蛋白。这些数据有力地表明Ywhae可能是 这些患者的ASD表型。14-3-3-ε在包括突起在内的神经元形态发生中的作用 形成，以前没有被分析过，仍然未知。因此，这一次的目标是 研究建议分析14-3-3ε在轴突中的体内新功能和分子靶点 形成，特别是轴突的起始和延伸，并阐明该细胞的分子机制 事件。我们推测，14-3-3ε在神经突起的起始和延伸过程中起重要作用。 通过与双皮质素结合和微管亲和力控制微管滑动和稳定性 调节蛋白激酶3(Mark3)。为了验证这一假设，我们建议使用各种各样的实验策略 包括宫内电穿孔、体外和体内延时活体成像、他莫昔芬诱导的Cre-loxP 系统和14-3-3ε条件基因敲除小鼠。我们有三个具体目标。在具体目标1中，我们将测试 14-3-3-ε调控轴突形成和突触发生的假说。在具体目标2中，假设 14-3-3ε通过与Dcx结合来调节MT滑动，从而调节皮质中轴突的起始 测试过。在特定的目标3中，我们将测试14-3-3ε通过结合到 Mark3并调节其活性。该项目的成功完成不仅将使人们了解到 对一种与ASD相关的新的人类遗传综合征的病因学研究 也大大提高了我们对14-3-3ε在轴突中的精确体内功能的理解 启蒙和延伸。

Project Summary/Abstract The formation of the intricate neuronal network in the brain requires precise neurogenesis and neuronal migration followed by neurite and spine formation during development. If neurite and spine formation is disrupted, it results in a wide range of diseases such as mental illnesses. Recently, patients with a microduplication of the 17p13.3 chromosome region have been reported and the number of patients exhibiting this syndrome has been increasing. Interestingly, the patients with this 17p13.3 microduplication syndrome show severe neurological and morphological defects, including, epilepsy, mental retardation and autism spectrum disorders (ASD). More interestingly, the studies analyzing this new human genetic syndrome clarified that the critical region spanning about 70kb is strongly associated with ASD, and this region contains a single gene, Ywhae, encoding the protein 14-3-3ε. These data strongly suggest that Ywhae might be responsible for the ASD phenotype in these patients. The functions of 14-3-3ε in neuronal morphogenesis including neurite formation, have not been previously analyzed and still remain unknown. Therefore, the objectives of this research proposal are to analyze the novel in vivo functions and molecular targets of 14-3-3ε in neurite formation, in particular neurite initiation and extension, and clarifying the molecular mechanisms in this cellular event. We hypothesize that 14-3-3ε plays an important role in neurite initiation as well as neurite extension by controlling microtubule (MT) sliding and stability through binding to Doublecortin (Dcx) and Microtubule affinity regulating kinase 3 (Mark3). To test this hypothesis, we propose to use a wide variety of experimental strategies including in utero electroporation, time-lapse live imaging in vitro and in vivo, tamoxifen-inducible Cre-loxP system, and 14-3-3ε conditional knockout mice. We have three specific aims. In the Specific Aim 1, we will test the hypothesis that 14-3-3ε regulates neurite formation and synaptogenesis. In Specific Aim 2, the hypothesis that 14-3-3ε regulates neurite initiation in the cortex by regulating MT sliding through binding to Dcx will be tested. In Specific Aim 3, we will test the hypothesis that 14-3-3ε regulates neurite extension by binding to Mark3 and regulating its activity. The successful completion of this project will not only provide understanding as to the etiology of a new human genetic syndrome strongly associating with ASD caused by the overexpression of 14-3-3ε but also significantly enhance our understanding of the precise in vivo functions of 14-3-3ε in neurite initiation and extension.