Nonproteolytic Polyubiquitin Chains at the Synapse

突触的非蛋白水解多聚泛素链

• 批准号: 9438416
• 负责人: Wei-Dong Yao
• 金额: $ 40.76万
• 依托单位: UPSTATE MEDICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-03-01 至 2020-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9438416
• 关键词: Adult; Anxiety; Autistic Disorder; Behavioral; Biochemical; Biological Assay; Brain; Brain Diseases; Chemicals; Cognitive; Dendritic Spines; Deubiquitinating Enzyme; Development; Disease; Electrophysiology (science); Emotional; Enzymes; Goals; In Vitro; Injury; Investigation; Link; Long-Term Depression; Lysine; Maintenance; Mediating; Memory; Modification; Molecular; Motivation; Mus; Mutant Strains Mice; Natural Immunity; Neuraxis; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neuroimmune; Neurons; Pathway interactions; Phenotype; Physiological; Polyubiquitin; Polyubiquitination; Prefrontal Cortex; Process; Property; Proteins; Psychomotor Performance; Rattus; Regulation; Rewards; Role; Scaffolding Protein; Schizophrenia; Short-Term Memory; Signal Transduction; Slice; Synapses; System; TNF Receptor-Associated Factors; TRAF6 gene; Testing; Transgenic Mice; Ubiquitin; Ubiquitination; adaptive immunity; autism spectrum disorder; behavior test; behavioral impairment; brain abnormalities; cellular imaging; experimental study; in vivo; long term memory; multicatalytic endopeptidase complex; multidisciplinary; nervous system disorder; neural circuit; neuropsychiatric disorder; novel; postsynaptic; pre-clinical; protein degradation; public health relevance; repaired; response; scaffold; social cognition; synaptogenesis; trafficking; treatment strategy; ubiquitin-protein ligase; virtual

 DESCRIPTION (provided by applicant): Altered assembly, function, and plasticity of synapses and neural circuits underlie cognitive, memory, and emotional deficits of essentially all neuropsychiatric and neurological diseases. A well-investigated mechanism that regulates synaptic protein turnover and synapse remodeling is the conventional ubiquitin-proteasome pathway, by which polyubiquitin chains conjugate to protein substrates (likely through lysine 48 (K48) of ubiquitin) and tag them for proteasomal degradation. A vastly overlooked ubiquitin modification in the central nervous system (CNS) is K63-linked polyubiquitination, an unconventional linkage mechanism generally believed not to target proteasomal degradation; rather, it regulates protein scaffolding, trafficking, and activity. Despite its recognized importace in cellular signaling mechanisms that mediate innate and adaptive immunity, virtually nothing is known about the role of this proteasome-independent polyubiquitination process in the CNS, especially synapses. Nonetheless, K63-linked ubiquitination is the second most abundant linkage in the rat brain, only slightly behind the K48 linkage. In addition, emerging evidence points to a link between K63-linked ubiquitination and a number of brain disorders. Thus, there is a need to investigate the mechanisms and roles of this nonproteolytic polyubiquitin topology in neurons and at synapse. Our preliminary studies indicate that K63-linked polyubiquitination is a fundamental mechanism regulating synapse assembly and plasticity and identify the postsynaptic scaffolding protein PSD-95 as the first substrate. We also identify a PSD-associated, K63-linkage-specific enzyme machinery that controls PSD-95 ubiquitination at synapses. The goals of this R01 application are to define the molecular details and functional consequences of PSD-95 K63 polyubiquitination (Aim 1), to delineate the role of K63 polyubiquitination in synapse development, function, remodeling, and plasticity (Aim 2), and to characterize the behavioral alterations in mice lacking K63-linkage-specific E3 ubiquitin ligase TRAF6 and deubiquitinase CYLD (Aim 3). A combination of molecular, biochemical, electrophysiological, and behavioral approaches will be employed. The proposed studies represent a fundamentally important conceptual breakthrough that opens up new avenues for investigation of synapse and circuit function and plasticity. The project has the potential to uncover new paradigm-shifting principles that govern neuro-immune interactions, which may contribute to abnormal brain wiring in neurodevelopmental disorders (such as schizophrenia and autism spectrum disorders) and neural circuit repair in the adult brain following injury. The information obtained will facilitate development of novel treatment strategies for these brain disorders.

 描述（由适用提供）：突触和神经元电路的组装，功能和可塑性基本上是所有神经精神疾病和神经系统疾病的认知，记忆和情绪缺陷。调节突触蛋白更新和突触重塑的良好评估机制是常规的泛素 - 蛋白酶体途径，通过该途径，通过该途径，多偶联蛋白链结合蛋白底物（可能是通过赖氨酸48（K48）的泛素）和蛋白酶质量的标记。中枢神经系统（CNS）中的泛素修饰非常忽略，是K63连接的多泛素化，这是一种非常规的连锁机制，通常被认为不靶向蛋白酶体降解。相反，它调节蛋白质脚手架，贩运和活动。尽管它在介导先天性和适应性免疫学的细胞信号传导机制中得到了公认的进口，但实际上，这种独立于蛋白酶体的多泛素化过程在中枢神经系统中，尤其是突触，几乎一无所知。尽管如此，K63连接的泛素化是大鼠大脑中第二大的链接，仅比K48链接略有略高。此外，新兴的证据表明，K63连接的泛素化与多种脑部疾病之间的联系。这就是需要研究这种非蛋白质溶解多泛素拓扑结构和突触时的机制和作用。我们的初步研究表明，K63连接的多泛素化是一种基本的机制，可以使突触组装和可塑性进行调节，并确定突触后脚手架蛋白PSD-95作为第一个底物。我们还确定了与PSD相关的K63-链接特异性酶机制，该酶机器控制着突触下的PSD-95泛素化。 The goals of this R01 application are to define the molecular details and functional consequences of PSD-95 K63 polyubiquitination (Aim 1), to delineate the role of K63 polyubiquitination in synapse development, function, remodeling, and plasticity (Aim 2), and to characterize the behavioral alterations in mice lacking K63-linkage-specific E3 ubiquitin ligase TRAF6 and去泛素酶CYLD（AIM 3）。分子，生化，电生理和行为方法的结合所提出的研究代表了从根本上重要的概念突破，为突触，电路功能和可塑性的投资提供了新的途径。该项目有可能发现负责神经免疫相互作用的新范式转移原理，这可能有助于神经发育障碍（例如精神分裂症和自闭症谱系）和成人大脑受伤后的神经元电路修复的脑接线异常。获得的信息将有助于制定这些脑疾病的新型治疗策略。