A New Model System for Adult Neurogenesis

项目摘要 在发育和体内平衡中，关键器官系统的祖干细胞经常分裂， 不对称的记忆的形成涉及成体神经发生，其中， 成年人的大脑不对称地分裂以产生新生的神经元。形成和回忆特定 记忆对我们的生存是不可或缺的。患有神经退行性疾病的患者，如 老年痴呆症表现出学习和记忆的严重破坏。因此，阐明发展 记忆形成的机械基础对于识别和防止 导致脑部疾病我们的长期目标是了解 在成人大脑中产生新的神经元。我们已经建立了一个新的模式生物来解决这个问题 问题，一个结合了哺乳动物的神经复杂性与实验室培养的便利性， 对一种昆虫进行基因操纵：蟋蟀双斑蟋蟀。在蟋蟀的大脑中，神经母细胞 学习和记忆所必需的神经干细胞。我们发现保守的 转录因子CREB在动物的学习和记忆中起着重要作用，它调节神经元的功能。 分子组织者奥斯卡，这两个基因都是长期记忆所必需的。我们假设 Oskar和CREB指导神经母细胞向神经元的适当不对称分裂，这允许长时间的 要建立长期记忆。我们将通过追求三个互补来检验这一假设。 具体目标。在目的1中，我们将确定oskar是否调节成体神经母细胞不对称细胞， 师.我们将使用CRISPR/Cas9和RNAi来消除oskar表达，并确定这是如何实现的。 利用原位杂交、免疫组织化学和共聚焦显微镜观察影响不对称细胞分裂 显微镜在目标2中，我们将确定Oskar在蟋蟀神经母细胞中的相互作用伙伴。到 为此，我们将评估已知基因的神经表达和长期记忆功能， 在其他细胞类型中与奥斯卡相互作用。我们还将采取公正的方法来确定相关的 oskar interactors通过使用单细胞RNA-seq来确定成神经细胞的完整转录组。 在目标3中，我们将定义CREB在调节成神经细胞分裂中的作用。我们将减少CREB 在成人大脑中的表达，并检查CREB的损失如何影响神经母细胞不对称细胞分裂。 这些实验的结果将揭示调节记忆的细胞机制 形成，这可能导致新的方法来改善记忆相关疾病。

PROJECT SUMMARY In development and homeostasis, progenitor stem cells of critical organ systems often divide asymmetrically. Memory formation involves adult neurogenesis, wherein progenitor stem cells in the adult brain divide asymmetrically to produce nascent neurons. The ability to form and recall specific memories is indispensable to our survival. Patients with neurodegenerative diseases such as Alzheimer’s exhibit drastic disruptions in learning and memory. As such, elucidating the developmental and mechanistic underpinnings of memory formation is critical to identifying and preventing processes that lead to brain disease. Our long-term objective is to understand the molecular mechanisms that generate new neurons in adult brains. We have established a new model organism for tackling this problem, one that combines the neural complexity of a mammal with the ease of laboratory culture and genetic manipulation of an insect: the cricket Gryllus bimaculatus. In the cricket brain, neuroblasts are neural stem cells necessary for learning and memory. We have discovered that the conserved transcription factor CREB, which plays a central role in animal learning and memory, regulates the molecular organizer oskar, and that both genes are required for long term memory. We hypothesize that Oskar and CREB direct proper asymmetric division of neuroblasts into neurons, which allows long term memories to be established. We will test this hypothesis through pursuit of three complementary Specific Aims. In Aim 1, we will determine whether oskar regulates adult neuroblast asymmetric cell division. We will use CRISPR/Cas9 and RNAi to abrogate oskar expression and determine how this affects asymmetric cell division using in situ hybridization, immunohistochemistry, and confocal microscopy. In Aim 2, we will identify the interacting partners of Oskar within Gryllus neuroblasts. To this end, we will assess the neural expression and long-term memory function of genes known to interact with oskar in other cell types. We will also take an unbiased approach to identifying relevant oskar interactors by using single cell RNA-seq to determine the complete transcriptome of neuroblasts. In Aim 3, we will define the role of CREB in regulating neuroblast division. We will reduce CREB expression in the adult brain and examine how CREB loss affects neuroblast asymmetric cell division. The results of these experiments will shed light on the cellular mechanisms that regulate memory formation, which could lead to novel approaches to ameliorate memory-related diseases.