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.

项目总结 记忆可以持续生物体的整个一生。数十亿个神经元之间的动态通信 突触是信息处理的基础，使记忆的编码和存储成为可能。中的更改 突触的强度和结构通过突触的可塑性被广泛推测为 记忆的形成和存储。研究已经确定了细胞信号事件和分子重排 是突触可塑性启动的基础。然而，关于分子的了解要少得多。 使突触的强度和记忆能够持续很长时间的基础。虽然初始突触 可塑性和长期记忆编码需要蛋白质合成，经过一段时间的巩固，记忆 存储变得独立于蛋白质合成或神经活动，这表明记忆存储在 非常稳定的分子实体。然而，在这段时间里，已知的大多数单个蛋白质 组成的突触会周转，在几小时到几天内被降解和更换。因此， 关于持久记忆的物质基础是什么，这个问题仍然存在。一 有可能是超长寿命蛋白质(LLP) 驻留在突触中，充当分子锚 保持定义给定记忆的突触强度或网络属性。 虽然之前的研究已经 证明了LLP在中枢神经系统中的存在，特别是在未分裂的核中 细胞，到目前为止还没有研究表明这些蛋白质是否存在于突触并对 建立和维持长期记忆。为了研究这一假设，我们设计了一个 基于蛋白质组学的无偏倚方法识别驻留在突触中的LLP并确定其神经元特征 功能。体内和体外都将使用稳定同位素代谢脉冲追逐标记来测量 神经元和突触蛋白质组的半衰期。这些实验将进一步与行为学相结合 以及研究记忆形成和神经元活动如何影响蛋白质的药物操作 营业额。确定的候选蛋白质将使用生化、细胞生物学、 电生理、成像和行为方法，以确定这些LLP如何有助于 突触/神经元功能和记忆。在细胞代谢活跃的环境中，我们知道 蛋白质可能会遭受氧化损伤。这种对有限责任合伙人的损害可能是脆弱性的一个来源，可能 在衰老过程中会导致功能衰退。这项提案中描述的实验将显著地 有助于我们理解LLP在大脑中的功能及其在记忆形成中的潜在作用， 长期储存和年龄相关的认知能力下降。