Localized mRNAs in Synaptic Plasticity

描述（申请人提供）：mRNA定位和调控翻译在轴突引导和突触可塑性中起核心作用。通过在空间上限制神经元内的基因表达，局部蛋白质合成允许生长锥和突触自主调节其结构和功能。本项目的长期目标是了解与学习相关的神经元可塑性和突触形成过程中局部翻译的细胞生物学和功能。我们的实验旨在解决以下四个问题：1)神经元过程中存在哪些mrna ？2) mrna如何在神经元内定位？3)突触如何调节本地化转录本的翻译？4)神经元中特定的局部翻译蛋白的功能是什么？我们在一个具有良好特征的、实验可处理的突触发生和学习相关突触可塑性模型中解决了这些问题：培养的泛子感觉运动神经元。我们的策略包括使用微阵列和高通量测序技术来识别神经元刺激后神经元过程中存在的mRNA，以及细胞生物学方法来可视化mRNA定位和活神经元中的调节翻译，以及RNA干扰方法来研究特定定位mRNA在突触形成和突触可塑性中的功能。我们提出的实验结果将为神经元内mRNA定位的细胞生物学以及特定定位转录本的功能提供见解。公共卫生相关性：我们建议研究大脑初始线路的细胞生物学基础以及在学习和记忆过程中发生的大脑线路变化。我们的研究结果将确定可能与大脑发育障碍有关的基因，如智力迟钝，以及许多学习和记忆改变的疾病。这些疾病包括脆性X型智力迟钝、脊髓性肌萎缩症、阿尔茨海默病、癫痫、吸毒成瘾和许多神经精神疾病。

DESCRIPTION (provided by applicant): mRNA localization and regulated translation play central roles in axon guidance and synaptic plasticity. By spatially restricting gene expression within neurons, local protein synthesis allows growth cones and synapses to autonomously regulate their structure and function. The long-term goals of this project are to understand the cell biology and function of local translation during learning-related neuronal plasticity and during synapse formation. Our experiments are designed to address the following four questions: 1) what mRNAs are present in neuronal processes? 2) How do mRNAs localize within neurons? 3) How is translation of localized transcripts regulated at the synapse? And 4) what is the function of specific locally translated proteins in neurons? We address these questions in a well-characterized, experimentally tractable model of synaptogenesis and learning-related synaptic plasticity: cultured Aplysia sensory-motor neurons. Our strategy involves the use of microarray and high throughput sequencing technologies to identify mRNAs that are present in neuronal processes following neuronal stimulation, together with cell biological approaches to visualize mRNA localization and regulated translation in living neurons and RNA interference approaches to study the function of specific localized mRNAs during synapse formation and synaptic plasticity. The results of our proposed experiments will provide insight into the cell biology of mRNA localization within neurons and into the function of specific localized transcripts. PUBLIC HEALTH RELEVANCE: We propose to investigate the cell biology underlying the initial wiring of the brain and the changes in brain wiring that occur during learning and memory. The results of our studies will identify genes that are likely to be involved in brain developmental disorders, such as mental retardation, and in the many diseases in which learning and memory are altered. Such diseases include Fragile X Mental Retardation, Spinal Muscular Atrophy, and Alzheimer's disease, epilepsy, drug addiction and many neuropsychiatric disorders.