Identification and validation of proteins with Siah-degron-motifs that are essential for neuronal migration.

具有 Siah-degron 基序的蛋白质的鉴定和验证对于神经元迁移至关重要。

• 批准号: 255966672
• 负责人: Dr. Jan Kullmann
• 金额: --
• 依托单位: Institut für Physiologische Chemie
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/255966672?language=en
• 关键词: Identification; validation; proteins; Siah; degron

Neuronal migration is essential for the morphogenesis of the developing brain and defective migration leads to profound developmental and cognitive disorders, such as lissencephalies with resulting epilepsy and mental retardation. In order to design strategies to prevent or treat such disorders, it is necessary to understand the molecular mechanisms that regulate neuronal motility and migration initiation. Recently, the Seven in Absentia homolog (Siah) E3 ubiquitin ligase has been identified as a novel regulator of the partitioning defective (PAR) proteins. Siah was isolated as a PAR-binding protein by a yeast-two hybrid screen and inhibits the germinal zone exit and migration of cerebellar granule neurons through the degradation of PAR3. An in silico and functional screen for further Siah targets revealed 22 proteins with Siah degrons and potential implications in neuronal migration. The aims of the proposed project are to validate whether these proteins are indeed degraded in a Siah-dependent manner and to test whether they are sufficient and/or necessary for germinal zone exit and neuronal migration. Siah-dependent degradation of the candidate proteins will be tested in a heterologous expression system (HEK293 cells) where Siah and a candidate protein will be expressed simultaneously. Afterwards the relevance of newly identified Siah-degraded proteins for germinal zone exit and radial migration of cerebellar granule neurons will be tested in organotypic cerebellar cultures. Subsequently the signaling pathways of the proteins that regulate germinal zone exit and/or neuronal migration will be determined via fluorescence-tagged adhesion receptors. Taken together this project will increase the knowledge about molecular mechanisms that control germinal zone exit and neuronal migration tremendously and could provide an avenue to discover new diagnostics and potential treatments for neuronal positioning disorders.

神经元迁移对于发育中的大脑的形态发生是必不可少的，并且有缺陷的迁移导致严重的发育和认知障碍，例如无脑畸形，从而导致癫痫和智力迟钝。为了设计预防或治疗这些疾病的策略，有必要了解调节神经元运动和迁移起始的分子机制。最近，七缺席同源物（Siah）E3泛素连接酶已被确定为一种新的调节分区缺陷（PAR）蛋白。Siah是通过酵母双杂交筛选分离的PAR结合蛋白，通过降解PAR 3抑制小脑颗粒神经元的生发带出口和迁移。进一步Siah靶点的计算机模拟和功能筛选揭示了22种具有Siah降解决定子的蛋白质和对神经元迁移的潜在影响。拟议项目的目的是验证这些蛋白质是否确实以Siah依赖的方式降解，并测试它们是否足以和/或必要的生发区退出和神经元迁移。将在异源表达系统（HEK293细胞）中测试候选蛋白的Siah依赖性降解，其中Siah和候选蛋白将同时表达。之后，将在器官型小脑培养物中测试新鉴定的Siah降解蛋白与小脑颗粒神经元的生发区出口和径向迁移的相关性。随后，通过荧光标记的粘附受体来确定调节生发区退出和/或神经元迁移的蛋白质的信号传导途径。总而言之，该项目将极大地增加有关控制生发区出口和神经元迁移的分子机制的知识，并可以为发现神经元定位障碍的新诊断方法和潜在治疗方法提供一种途径。