Generation of a dual transgenic/viral system to characterize multiple engrams in a single mouse

生成双转基因/病毒系统来表征单个小鼠中的多个印迹

• 批准号: 10670679
• 负责人: Michelle Stackmann
• 金额: $ 4.87万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10670679
• 关键词: Address; Alzheimer' s Disease; Automobile Driving; Behavioral; Biological; Brain; Brain region; Cells; Chemicals; Computer Models; Computing Methodologies; Development; Disease; Doxycycline; Electrophysiology (science); Engineering; Environment; Exhibits; Exposure to; Generations; Genetic; Goals; Hippocampus; Immediate-Early Genes; Knowledge; Label; Laboratories; Laboratory Study; Latina; Learning; Measures; Memory; Memory Disorders; Modernization; Mouse Protein; Mus; Neurobiology; Neuronal Dysfunction; Neurons; Pattern; Phase; Population; Population Dynamics; Positioning Attribute; Postdoctoral Fellow; Property; Research; Research Personnel; Research Project Grants; Research Proposals; Role; Scientist; Stimulus; Synapses; System; Techniques; Technology; Testing; Time; Training; Transgenic Organisms; Viral; Visualization; Whole-Cell Recordings; career; combinatorial; computerized tools; conditioned fear; dentate gyrus; experience; in vivo; memory encoding; memory process; memory retrieval; neural; neurobiological mechanism; new technology; novel; recruit; skills; tool

PROJECT SUMMARY / ABSTRACT Memories are thought to be stored through lasting physical and chemical changes in the brain. The biological substrate of a memory is known as an engram or memory trace. An engram is the neural ensemble activated during learning and whose reactivation by the original stimulus results in memory retrieval. Modern technological advances have allowed scientists to visualize and manipulate engrams, showing that they exist in various brain regions and their content can be altered. These strategies have taken advantage of immediate early genes (IEGs) such as Arc, which are expressed upon neuronal activation. Transgenic and viral tools, such as the ArcCreERT2 mice and the Robust Activity Marking (RAM) system, have been engineered to label cells in an activity-dependent manner. Although these tools have furthered our understanding of how a single engram is represented in the brain, they have not been combined to label multiple engrams. Thus, this research plan focuses on identifying multiple engrams in a single mouse and characterizing the synaptic mechanisms underlying multiple engram storage. To achieve these goals, I have developed and characterized a novel viral strategy that allows for the labeling of previously activated Arc+ ensembles. I have combined this viral strategy with the ArcCreERT2 x enhanced yellow fluorescent protein (EYFP) mice to ultimately label multiple Arc+ ensembles and visualize multiple engrams in a single mouse. Using this novel combinatorial transgenic/viral strategy, I have shown that the engrams of exposures to a single environment are reactivated to a greater extent those representing exposures to different environments. Moreover, the synaptic mechanisms that contribute to the storage of multiple memories in the hippocampus is poorly understood. To this end, during the F99 phase, I propose to use ex vivo electrophysiology to identify synaptic signatures (e.g., excitability, connectivity) of co-labeled Arc+ ensembles. A greater understanding of the synaptic properties of the ensembles that are recruited to multiple engrams will contribute to our overall understanding of how memories are co-stored in the brain. For the K00 phase, I will investigate the population-level dynamics of hippocampal ensembles during memory processes using large-scale recording techniques and computational models. These studies will illuminate our understanding of the computations performed by the hippocampus that support memory processes and will allow us to generate more precise hypotheses for how these computations might go awry in memory-related disorders, such as Alzheimer’s Disease (AD). The completion of this research proposal will provide me with training in electrophysiology, strengthen my technical and professional skills, and facilitate my transition to a postdoctoral position in a laboratory that studies population dynamics of neural ensembles and computational methods.

项目总结/摘要 记忆被认为是通过大脑中持久的物理和化学变化来储存的。生物 存储器基底被称为记忆痕迹或存储器迹线。记忆印记是被激活的 在学习过程中，它被原始刺激重新激活，导致记忆恢复。现代 技术的进步使科学家能够可视化和操纵记忆痕迹，显示它们的存在 在不同的大脑区域，它们的内容可以改变。这些战略利用了直接的 早期基因（IEG），如Arc，其在神经元激活时表达。转基因和病毒工具， 例如ArcCreERT 2小鼠和健壮活动标记（RAM）系统，已经被设计用于标记 细胞以活性依赖的方式。尽管这些工具使我们进一步了解了一个单一的 由于这些记忆印记在大脑中被表示，因此它们尚未被组合以标记多个记忆印记。因此，这 一项研究计划的重点是识别一只老鼠的多个记忆痕迹，并描述突触的特征。 多重记忆印记存储的潜在机制。为了实现这些目标，我开发并描述了 一种新的病毒策略，允许标记先前激活的Arc+集合。我把这些 使用ArcCreERT 2 x增强型黄色荧光蛋白（EYFP）小鼠的病毒策略， 多个Arc+集成，并在单个小鼠中可视化多个印迹。使用这种新颖的组合 转基因/病毒策略，我已经表明，暴露于单一环境的痕迹被重新激活， 在更大程度上代表暴露于不同环境的那些。此外，突触 对海马体中多种记忆的储存机制知之甚少。到 为此，在F99阶段，我建议使用离体电生理学来识别突触特征（例如， 兴奋性、连接性）。更深入地了解突触的特性 被招募到多个记忆印痕中的合奏将有助于我们全面了解 记忆是共同储存在大脑中的对于K 00阶段，我将研究 使用大规模记录技术和计算技术， 模型这些研究将阐明我们对海马体执行的计算的理解 支持记忆过程，并允许我们产生更精确的假设， 计算可能会在记忆相关疾病中出错，如阿尔茨海默病（AD）。完成 这项研究计划将为我提供电生理学方面的培训，加强我的技术和 专业技能，并帮助我过渡到一个研究人口的实验室的博士后职位 神经系综动力学和计算方法。