A study of ZCCHC17 regulation of synaptic genes in Alzheimers disease

ZCCHC17对阿尔茨海默病突触基因调控的研究

• 批准号: 8757603
• 负责人: Andrew Franklin Teich
• 金额: $ 12万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8757603
• 关键词: Adult; Affect; Alzheimer' s Disease; Amyloid; Amyloid Proteins; Amyloid beta-Protein Precursor; Atrophic; Behavior; Binding; Bioinformatics; Brain; Cell Death; Cell Nucleus; Cells; ChIP-seq; Computer Analysis; DNA; Data; Dementia; Disease; Down-Regulation; Environment; Functional disorder; Future; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Goals; Health; Heart; Hippocampus (Brain); Human; Lasers; Lead; Link; Memory; Memory Loss; Messenger RNA; Molecular Profiling; Mus; Mutate; Neurons; Northern Blotting; Nuclear Localization Signal; Nuclear Structure; Nucleic Acid Regulatory Sequences; Patients; Positioning Attribute; Proteins; Publications; Publishing; Regulation; Role; Skeletal Muscle; Small Interfering RNA; Synapses; Synaptic plasticity; Techniques; Testing; Tg2576; Therapeutic; Thymus Gland; Tissues; Transcript; Variant; Western Blotting; Work; Zinc Fingers; base; brain tissue; disorder control; functional restoration; human tissue; knock-down; mouse model; novel; prevent; promoter; research study; synaptic function; tool; transcription factor

DESCRIPTION (provided by applicant): Accumulating evidence suggests that Alzheimer's Disease (AD) begins as a synaptic disorder. This view is supported by work showing that toxic levels of β-amyloid protein are associated with synaptic dysfunction and memory loss long before atrophy and cell death occur. Inspired by this observation, I have used bioinformatics tools to search for causes of synaptic dysfunction in AD. I have identified a transcription factor called ZCCHC17 that is reduced in AD brain tissue, and my hypothesis is that low levels of this transcription factor contribute to synaptic dysfunction in AD. My hypothesis is supported by my preliminary data (see below). Based on its structure and nuclear localization, ZCCHC17 is predicted to regulate gene expression. However, it is not well studied, and has not previously been linked to AD. Further study of ZCCHC17's role in synaptic dysfunction in AD may provide a therapeutic strategy to rescue synaptic plasticity and memory in this disease. I arrived at my hypothesis using a combination of computational and wet-lab techniques. I began by using novel statistical techniques to screen RNA expression profiles from laser-dissected neurons taken from human AD and control brains. My goal was to identify transcription factors that: 1) Are predicted to regulate a large number of synaptic targets, and 2) Are predicted to have impaired function in AD. My strongest candidate from this work is ZCCHC17. I have now shown that 1) ZCCHC17 protein levels are decreased in AD brain homogenate, and 2) ZCCHC17 is primarily located in neuronal nuclei and is decreased in AD. Although compelling, this data is still only correlational. Since ZCCHC17 is not well studied, the goal of this proposal is to generate foundational data that supports my hypothesis that ZCCHC17 is important for synaptic function and is impaired in AD. This data will justify a more in-depth study of ZCCHC17 in a future project. In Aim 1, I will test the hypothesis that ZCCHC17 is a transcription factor that regulates synaptic genes. I will do this first using ChIP-seq, which will allow me to determine if ZCCHC17 binds to DNA. If ZCCHC17 binds to DNA regulatory regions, then this supports the hypothesis that ZCCHC17 is a transcription factor that regulates gene expression. I will perform ChIP-seq in several different tissues in order to increase my understanding of ZCCHC17's role in neuronal function (human tissue, SY5Y cells, mouse hippocampal neurons, and adult mouse brain). I will also perform siRNA knock-down of ZCCHC17 in the last three tissues. If siRNA knock- down of ZCCHC17 causes reduced expression of ZCCHC17's predicted synaptic targets, then this supports the hypothesis that ZCCHC17 regulates the expression of these synaptic genes. In Aim 2, I will test the hypothesis that elevated β-amyloid levels lead to lower ZCCHC17 protein levels. I have preliminary data supporting this hypothesis, and I will directly test this hypothesis in SY5Y cells, mouse hippocampal neuronal cultures, and in adult mouse cortex. If this prediction is true, then this supports the hypothesis that β-amyloid impairs ZCCHC17 function.

描述（由申请人提供）：越来越多的证据表明阿尔茨海默氏病（AD）始于突触障碍。这一观点得到了研究的支持，该研究表明，早在萎缩和细胞死亡发生之前，β-淀粉样蛋白的毒性水平就与突触功能障碍和记忆丧失有关。受这一观察的启发，我使用生物信息学工具来寻找 AD 突触功能障碍的原因。我发现了一种称为 ZCCHC17 的转录因子，它在 AD 脑组织中减少，我的假设是，这种转录因子的低水平会导致 AD 中的突触功能障碍。我的假设得到了我的初步数据的支持（见下文）。根据其结构和核定位，ZCCHC17 预计可调节基因表达。然而，它还没有得到充分研究，之前也没有与 AD 联系起来。进一步研究 ZCCHC17 在 AD 突触功能障碍中的作用可能为挽救这种疾病的突触可塑性和记忆提供治疗策略。我结合计算和湿实验室技术得出了我的假设。我首先使用新颖的统计技术来筛选取自人类 AD 和对照大脑的激光解剖神经元的 RNA 表达谱。我的目标是确定具有以下特征的转录因子：1) 预计可调节大量突触靶标，2) 预计在 AD 中功能受损。这项工作中我最强的候选者是 ZCCHC17。我现在已经证明，1) ZCCHC17 蛋白水平在 AD 脑匀浆中降低，2) ZCCHC17 主要位于神经元细胞核中，并且在 AD 中降低。尽管令人信服，但该数据仍然只是相关性的。由于 ZCCHC17 尚未得到充分研究，该提案的目标是生成支持我的假设的基础数据，即 ZCCHC17 对突触功能很重要，并且在 AD 中受损。这些数据将证明在未来的项目中对 ZCCHC17 进行更深入的研究是合理的。在目标 1 中，我将检验 ZCCHC17 是调节突触基因的转录因子这一假设。我将首先使用 ChIP-seq 进行此操作，这将使我能够确定 ZCCHC17 是否与 DNA 结合。如果 ZCCHC17 与 DNA 调节区结合，那么这支持了 ZCCHC17 是调节基因表达的转录因子的假设。我将在几种不同的组织中进行 ChIP-seq，以加深对 ZCCHC17 在神经元功能（人体组织、SY5Y 细胞、小鼠海马神经元和成年小鼠大脑）中的作用的理解。我还将在最后三个组织中进行 ZCCHC17 的 siRNA 敲除。如果 ZCCHC17 的 siRNA 敲除导致 ZCCHC17 预测的突触靶标的表达减少，则这支持了 ZCCHC17 调节这些突触基因表达的假设。在目标 2 中，我将检验以下假设：β-淀粉样蛋白水平升高会导致 ZCCHC17 蛋白水平降低。我有初步数据支持这个假设，我将直接在 SY5Y 细胞、小鼠海马神经元培养物和成年小鼠皮层中测试这个假设。如果这一预测属实，则支持 β-淀粉样蛋白损害 ZCCHC17 功能的假设。