A multi-modal, brain-wide atlas of astrocyte diversity across developmental stages and model species

项目总结 星形胶质细胞影响神经元回路的组装和功能，并已被证明响应、调节和 驱病病机。尽管如此，人们对脑区星形胶质细胞的多样性知之甚少， 发展和物种。然而，最近的单细胞RNA测序研究表明，星形胶质细胞 在整个大脑中具有显著的转录异质性。详细的分子和细胞特征 以确定分子定义的星形胶质细胞亚群是否 在健康和疾病两方面都有不同的功能。因此，该项目的目标是使用尖端技术来 描述星形胶质细胞亚群的转录、结构和功能多样性 小鼠和绒猴大脑的发育阶段和与疾病相关的脑区域。通过进行一次 详细分析了年轻成年绒猴大脑八个区域的超过7万个星形细胞核，我有 发现星形胶质细胞之间显著的区域异质性，特别是皮质和皮质下之间 地区。在这项提议中，我的目标是取得三项重大进展：a)绘制星形胶质细胞区域进化图 不同发育阶段的异质性，b)比较啮齿动物和非人灵长类之间的异质性 C)表征转录上不同的星形胶质细胞亚型的功能特性。致信地址 其中前两个，我将对胚胎，新生儿， 幼猴、幼猴和幼鼠。为了解决第三个问题，我将使用扩展显微镜来评估 分子定义的星形胶质细胞亚型是否具有不同的形态、突触的包膜和/或 离子通道在纳米尺度上的配置。此外，我将成像星形胶质细胞的钙动力学，考虑到 急性脑片星形胶质细胞用来调节神经元网络的信号过程的关键组成部分 从小鼠和绒猴中鉴定转录定义的星形胶质细胞的功能多样性 子类型。这项拟议的研究将标志着第一个跨物种、跨发展、跨区域的分子 使用一致的实验和计算方法对脑细胞进行分析，并将创造新的 啮齿动物和非人类星形胶质细胞跨脑区异质性发展的认识 灵长类动物。重要的是，星形胶质细胞亚群的这种详细的分子和细胞特征将 促进他们对神经发育和精神病学的基础和翻译研究的精确操作 精神错乱。我将在冯国平博士和埃德·博伊登博士在大脑和认知方面的实验室进行这个项目 麻省理工学院科学系。冯和博伊登的实验室包含所有 拟议项目所需的设备。所有必要的实验室和实验室培训 计算技术将由高级实验室成员提供，或通过与BCS的其他实验室合作提供 和外部合作者。冯和博伊登实验室、BCS和麻省理工学院提供了非凡的科学和 专业发展资源，以促进我成功地过渡到博士后奖学金。

PROJECT SUMMARY Astrocytes influence neuronal circuit assembly and function and have been shown to respond, modulate, and drive disease pathogenesis. Despite this, relatively little is known about astrocyte diversity across brain regions, development, and species. However, recent single-cell RNA sequencing studies demonstrate that astrocytes have significant transcriptomic heterogeneity across the brain. Detailed molecular and cellular characterization of these subpopulations is needed to determine whether molecularly-defined astrocyte subpopulations serve distinct functions in both health and disease. Thus, the goal of this project is to use cutting-edge techniques to characterize the transcriptomic, structural, and functional diversity of astrocyte subpopulations across developmental stages and disease-relevant brain regions in the mouse and marmoset brain. By conducting a detailed analysis of over 70,000 astrocyte nuclei across eight brain regions in the young adult marmoset, I have discovered striking regional heterogeneity among astrocytes, particularly between cortical and subcortical regions. In this proposal, I aim to make three significant advances: a) map the evolution of astrocyte regional heterogeneity across development, b) compare this heterogeneity between rodent and non-human primate species, and c) characterize the functional identities of transcriptomically distinct astrocyte subtypes. To address the first two of these, I will conduct single-nucleus RNA sequencing of four brain regions in the embryo, neonate, juvenile, and adolescent marmoset and mouse. To address the third, I will use expansion microscopy to assess whether molecularly-defined astrocyte subtypes have distinct morphologies, ensheathment of synapses, and/or configuration of ion channels at the nanoscale. Additionally, I will image astrocyte calcium dynamics, considered key components of signaling processes used by astrocytes to regulate neuronal networks, in acute brain slices from both mouse and marmoset to characterize the functional diversity of transcriptomically-defined astrocyte subtypes. The proposed study will mark the first cross-species, cross-development, cross-region molecular profile of brain cells using consistent experimental and computational methodology, and will create new knowledge about the development of astrocyte heterogeneity across brain regions in rodents and non-human primates. Importantly, this detailed molecular and cellular characterization of astrocyte subpopulations will facilitate their precise manipulation for basic and translational research on neurodevelopmental and psychiatric disorders. I will carry out this project in the labs of Dr. Guoping Feng and Dr. Ed Boyden in the Brain and Cognitive Sciences Department at the Massachusetts Institute of Technology. The Feng and Boyden labs contain all required equipment for the proposed project. All necessary training regarding required laboratory and computational techniques will be provided by senior lab members or through collaboration with other labs in BCS and external collaborators. The Feng and Boyden labs, BCS, and MIT offer exceptional scientific and professional development resources to facilitate my successful transition into a postdoctoral fellowship.