Mechanisms of Neurodegeneration

神经退行性变的机制

• 批准号: 8841838
• 负责人: J. Marie Hardwick
• 金额: $ 35.44万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8841838
• 关键词: Adolescence; Aging; Amino Acid Sequence; Amino Acids; Attention; Autophagocytosis; Autophagosome; BTB/POZ Domain; Biochemical; Brain; Cell Death; Cell Line; Cessation of life; Child; Clinical; Collection; Complex; Cytoplasmic Tail; Defect; Development; Disease; Employee Strikes; Epilepsy; Etiology; Family; Family member; Feedback; GABA-B Receptor; Genes; Genetic Engineering; Genetic Screening; Genetic study; Glean; Goals; Health; Homologous Gene; Human; Individual; Informatics; Knock-out; Knockout Mice; Link; Magnetic Resonance Imaging; Mammalian Cell; Mammals; Membrane; Microscopy; Mitochondria; Modeling; Molecular; Mutation; Myoclonus; N-terminal; Nerve Degeneration; Nervous system structure; Neuronal Ceroid-Lipofuscinosis; Neurons; Neurotransmitters; Nutrient; Organelles; Pathogenesis; Pathway interactions; Patients; Phosphotransferases; Population; Positioning Attribute; Process; Progressive Myoclonic Epilepsies; Protein Family; Proteins; PubMed; Recycling; Reporting; Research; Role; Saccharomyces cerevisiae; Seizures; Signal Transduction; Sirolimus; Stress; Syndrome; Testing; Therapeutic; Translating; Yeasts; base; detection of nutrient; economic impact; fungus; gamma-Aminobutyric Acid; genome-wide; human disease; human genome sequencing; infancy; insight; member; mouse model; mutant; nervous system disorder; neuron loss; novel; novel strategies; protein aggregate; response; success; tumorigenesis; yeast genetics

DESCRIPTION (provided by applicant): There are many different underlying causes of epilepsy and associated neurodegeneration, most of which are still unknown. Identification of epilepsy disease genes has provided valuable insight into disease mechanisms. However, few epilepsy genes are understood at a level that approaches a molecular understanding sufficient to help guide development of effective therapeutics, and thus far most successes are limited to channel proteins. Rapid expansion of human genome sequencing has identified new epilepsy genes of unknown function, and new approaches are needed to delineate their mechanisms of disease causality. A case in point is the human KCTD7 gene, a newly designated epilepsy/neurodegeneration gene. Mutations in KCTD7 cause progressive myoclonic epilepsy (EPM3), infantile onset neuronal ceroid lipofuscinosis (CLN14), and possibly other disorders. However, except for a growing number of reports identifying KCTD7 mutations in patients, essentially nothing is known about the molecular functions of KCTD7 (8 hits for "KCTD7" in PubMed). Our goal is to uncover the underlying mechanisms of KCTD7 based on novel insights gained from our studies in yeast (Saccharomyces cerevisiae), combined with mammalian models of neuronal cell death, mitochondrial function and autophagy. A yeast genetic screen in our lab uncovered new functions for a yeast gene that has significant amino acid sequence similarity to the 24-member KCTD family of poorly characterized human proteins. KCTD7 is expressed specifically in neurons of the brain. Our studies in yeast suggest new unexpected functions for human KCTD7 in nutrient sensing and autophagy. We predict that the results of the proposed project will have a significant impact on the understanding of basic molecular mechanisms of KCTD7 as well as the mechanisms that underlie neurodegeneration and epilepsy in patients. In Aim 1, we will use microscopy and biochemical approaches to establish the role of human KCTD7 in nutrient sensing and autophagy in cell lines and primary neurons. In Aim 2, we will delineate mechanisms of KCTD7 activation and function, and in Aim 3 we will test the relevance of these molecular mechanisms by analyzing a new mouse model genetically engineered to mimic EPM3/CLN14 patients. We also expect to provide valuable insight into other neurodegenerative processes, and to advance the utility of mouse models in epilepsy research.

描述（由申请人提供）：癫痫和相关神经变性有许多不同的根本原因，其中大多数仍然未知。癫痫疾病基因的鉴定为了解疾病机制提供了宝贵的见解。然而，很少有人对癫痫基因的了解达到足以帮助指导有效治疗方法开发的分子理解水平，因此迄今为止大多数成功仅限于通道蛋白。人类基因组测序的快速扩展已经识别出功能未知的新癫痫基因，并且需要新的方法来描述其疾病因果关系的机制。人类 KCTD7 基因就是一个典型的例子，它是一种新指定的癫痫/神经退行性疾病基因。 KCTD7 突变会导致进行性肌阵挛性癫痫 (EPM3)、婴儿期发病的神经元蜡样质脂褐质沉积症 (CLN14) 以及可能的其他疾病。然而，除了越来越多的报告识别出患者中的 KCTD7 突变外，基本上对 KCTD7 的分子功能一无所知（PubMed 中“KCTD7”有 8 次点击）。我们的目标是基于我们在酵母（酿酒酵母）研究中获得的新见解，结合神经元细胞死亡、线粒体功能和自噬的哺乳动物模型，揭示 KCTD7 的潜在机制。我们实验室的酵母遗传筛选发现了一种酵母基因的新功能，该基因与由 24 个成员组成的 KCTD 人类蛋白质家族具有显着的氨基酸序列相似性。 KCTD7 在大脑神经元中特异性表达。我们对酵母的研究表明，人类 KCTD7 在营养感应和自噬方面具有意想不到的新功能。我们预测该项目的结果将对 KCTD7 的基本分子机制以及患者神经变性和癫痫的机制的理解产生重大影响。在目标 1 中，我们将使用显微镜和生化方法来确定人 KCTD7 在细胞系和原代神经元的营养感应和自噬中的作用。在目标 2 中，我们将描述 KCTD7 激活和功能的机制，在目标 3 中，我们将通过分析经过基因工程改造模拟 EPM3/CLN14 患者的新小鼠模型来测试这些分子机制的相关性。我们还希望为其他神经退行性过程提供有价值的见解，并提高小鼠模型在癫痫研究中的实用性。