Long-Lived Synaptic Proteins

长寿命突触蛋白

• 批准号: 9333671
• 负责人: Richard L Huganir
• 金额: $ 61.07万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-05 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9333671
• 关键词: Address; Age-associated memory impairment; Aging; Amino Acids; Behavior; Behavior Control; Behavioral; Biochemical; Biological; Brain; CRISPR/Cas technology; Cell Nucleus; Cells; Code; Communication; Culture Media; DNA; Diet; Electrophysiology (science); Environment; Event; Hour; Human; Image; In Vitro; Individual; Interphase Cell; Isotope Labeling; Knockout Mice; Label; Learning; Long-Term Depression; Long-Term Potentiation; Maintenance; Mass Spectrum Analysis; Measures; Memory; Metabolic; Methodology; Molecular; Mus; Mutation; Neuraxis; Neurodevelopmental Disorder; Neurons; Organism; Peptides; Pharmacology; Physiologic pulse; Property; Protein Biosynthesis; Proteins; Proteome; Proteomics; Regulation; Research; Role; Signal Transduction; Source; Structure; Synapses; Synaptic plasticity; Testing; Time; base; behavioral pharmacology; design; experimental study; functional decline; in vivo; information processing; interest; long term memory; molecular rearrangement; neuropsychiatric disorder; oxidative damage; protein degradation; protein function; relating to nervous system; repaired; stable isotope; synaptic function; synaptogenesis

PROJECT SUMMARY Memories can last the entire lifetime of an organism. Dynamic communication among billions of neurons at synapses underlies information processing and enables the coding and storage of memory. Changes in synapse strength and structure through synaptic plasticity are widely speculated as the cellular basis of memory formation and storage. Studies have identified cellular signaling events and molecular rearrangements underlying the initiation of synaptic plasticity. However, considerably less is known regarding the molecular basis enabling synaptic strength and memories to persist for extended periods of time. While initial synaptic plasticity and long-term memory coding requires protein synthesis, following a period of consolidation, memory storage becomes independent of protein synthesis or neural activity, suggesting that the memory is stored in a remarkably stable molecular entity. During this time, however, most of the individual proteins that are known to make up the synapse will turnover, being degraded and replaced within hours to a few days. Therefore the question remains as to what physical substrates underlie the persistence of long-lasting memories. One possibility is that exceptionally long-lived proteins (LLPs) reside in synapses and act as molecular anchors to maintain the synaptic strength or a network property that defines a given memory. While previous studies have demonstrated the existence of LLPs in the central nervous system, particularly in the nuclei of non-dividing cells, no studies to date have addressed whether such proteins exist at synapses and contribute to the establishment and maintenance of long-term memories. To investigate this hypothesis we designed an unbiased, proteomics-based approach to identify LLPs resident in synapses and characterize their neuronal function. Stable isotope metabolic pulse-chase labeling will be used both in vivo and in vitro to measure the half-lives of the neuronal and synaptic proteomes. These experiments will further be combined with behavioral and pharmacological manipulations to examine how memory formation and neuronal activity influence protein turnover. Identified candidate proteins will be characterized using biochemical, cell-biological, electrophysiological, imaging and behavioral methodologies to determine how these LLPs contribute to synaptic/neuronal function and memory. Within the metabolically active environment of the cell it is known that proteins can undergo oxidative damage. Such damage to LLPs could be a source of vulnerability that may contribute to functional decline during aging. The experiments described in this proposal will significantly contribute to our understanding of LLP functions in the brain and their potential role in for memory formation, long-term storage and age-related cognitive decline.

项目摘要 回忆可以持续一个生物体的整个生命。数十亿个神经元之间的动态沟通 突触是信息处理的基础，并启用了内存的编码和存储。变更 突触强度和通过突触可塑性的结构被广泛推测为细胞基础 内存形成和存储。研究已经确定了细胞信号传导事件和分子重排 突触可塑性的启动。但是，关于分子的已知要少得多 基础使突触力量和记忆长时间持续。而初始突触 在一段时间的固结，记忆期之后，可塑性和长期记忆编码需要蛋白质合成 存储变得独立于蛋白质合成或神经活动，表明记忆存储在A 非常稳定的分子实体。但是，在此期间，大多数已知的单个蛋白质 弥补突触将会流动，在几个小时内退化并更换几天。因此 关于什么物理底物是长期记忆的持久性的问题。一 可能性是异常长寿命的蛋白质（LLP） 居住在突触中，充当分子锚 维护定义给定内存的突触强度或网络属性。 以前的研究有 证明了中枢神经系统中LLP的存在，特别是在非分裂的核中 细胞，迄今为止尚无研究尚未解决这种蛋白质是否存在于突触时，并有助于 长期记忆的建立和维护。为了研究这一假设，我们设计了 公正的，基于蛋白质组学的方法来识别居住在突触中的LLP并表征其神经元 功能。稳定的同位素代谢脉冲练习标记将在体内和体外使用，以测量 神经元和突触蛋白质组的半衰期。这些实验将与行为进一步结合 和药理操作以检查记忆形成和神经元活性如何影响蛋白 周转。确定的候选蛋白将使用生化，细胞生物学， 电生理，成像和行为方法论，以确定这些LLP如何贡献 突触/神经元功能和内存。在细胞的代谢活性环境中，已知 蛋白质会受到氧化损伤。对LLP的这种损害可能是脆弱性的根源 在衰老期间有助于功能下降。本提案中描述的实验将大大显着 有助于我们对大脑中LLP功能的理解及其在记忆形成中的潜在作用， 长期存储和与年龄有关的认知能力下降。