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.

项目概要 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，并支持记忆的编码和存储。变化 通过突触可塑性的突触强度和结构被广泛推测为突触的细胞基础 记忆的形成和储存。研究已确定细胞信号传导事件和分子重排 突触可塑性启动的基础。然而，人们对分子的了解却少之又少。 使突触强度和记忆能够长期持续的基础。当初始突触 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，这表明记忆存储在一个 非常稳定的分子实体。然而，在此期间，大多数已知的单个蛋白质 突触会在几小时到几天内周转、降解和替换。因此 问题仍然在于，持久记忆的持久性背后的物理基础是什么。一 可能性是异常长寿的蛋白质（LLP） 驻留在突触中并充当分子锚 维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，特别是在不分裂的细胞核中 细胞中，迄今为止还没有研究表明此类蛋白质是否存在于突触中并有助于 长期记忆的建立和维持。为了研究这个假设，我们设计了一个 公正的、基于蛋白质组学的方法来识别突触中的 LLP 并表征其神经元 功能。稳定同位素代谢脉冲追踪标记将用于体内和体外测量 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 和药理学操作来检查记忆形成和神经元活动如何影响蛋白质 周转。将使用生物化学、细胞生物学、 电生理学、成像和行为方法学，以确定这些 LLP 如何有助于 突触/神经元功能和记忆。在细胞的代谢活跃环境中，已知 蛋白质可能会受到氧化损伤。对有限责任合伙企业的此类损害可能是脆弱性的根源， 导致衰老过程中功能衰退。本提案中描述的实验将显着 有助于我们了解大脑中的 LLP 功能及其在记忆形成中的潜在作用， 长期储存和与年龄相关的认知能力下降。