Genetic Studies of Cortex Structure and Development

项目总结 大脑皮层调节失调是人类发育障碍的核心，如癫痫、精神障碍 缺乏症、自闭症和精神分裂症。在发育过程中，皮质祖细胞产生投射 不同皮质亚区的神经元。了解控制发育的遗传回路 这些神经元的功能为解释人类等位基因变体提供了必要的基础 更多的是有神经精神障碍的人。为了阐明这一遗传回路，我们必须定义 转录因子(TF)、调控元件及其控制的编码区。建议数 集中于大脑皮层区域化的研究，涉及到系统地识别转录因子，以及 转录因子下游的调控元件和基因。目前，少数TF的区域规范功能 在胚胎中，皮质祖细胞是已知的，而对它们的直接转录靶标知之甚少。 这些转录因子控制的调控元件的性质以及整合的转录电路 这些细胞的发育和功能。在这里，我们建议进军这些组件中的每一个 调节大脑皮层发育的转铁蛋白等级。此外，我们的目标是阐明转录机制。 通过它，皮质祖细胞的图案被传递到皮质神经元，并在皮质神经元中保持。我们 假设在脑室区域、脑室下区域和皮质板中起作用的增强剂 差异结合的转录因子，驱动有丝分裂后皮质神经元中区域/层特异性基因的表达。 增强剂作为蛋白质结合模块，将转录因子的吻尾梯度转化为皮质 神经前体细胞在大脑皮层神经元中的区域特异性表达。在这里，我们主要关注转录 控制大脑皮层不同区域产生的机制(大脑皮层区域化)。这个 五个具体目标延伸到我们早先关于通过成纤维细胞生长因子信号对皮质祖细胞进行区域化的工作， TFS和增强子元件。在这里，我们通过定义皮质模式的转录调控来研究 TFS和其他受COUPTF1、EMX2和PAX6调控的基因(目标1)。然后我们用染色质 免疫沉淀-DNA测序(CHIP-SEQ)以确定调控元件(RE)和基因靶 COUPTF1、EMX2和PAX6(目标2)。接下来，我们使用荧光激活细胞分选(FACS)来纯化细胞 用组蛋白从VZ、SVZ、CP和5&6层阐明RES(和基因)的表观基因组状态 芯片序列这将有助于我们理解传递区域图案信息的分子机制 从皮质祖细胞到神经元(目标3)。最后，我们定义了与大脑皮层模式相关的RES的功能 使用转基因小鼠评估RE活性(AIMS 4)和RES缺失以确定它们在基因调控中的作用 (目标5)。一旦与人类基因信息相结合，这将使我们能够获得关于如何 特定基因网络的异常会导致人类神经精神障碍。

PROJECT SUMMARY Dysregulation of the cerebral cortex is central to human developmental disorders such as epilepsy, mental deficiency, autism and schizophrenia. During development, cortical progenitors generate the projection neurons of the different cortical subdivisions. Understanding the genetic circuitry controlling the development and function of these neurons provides an essential foundation for interpreting human allele variants that are enriched in people who have neuropsychiatric disorders. To elucidate this genetic circuitry, we must define the transcription factors (TF), and regulatory elements and of the coding regions that they control. The proposed research, which concentrates on cortical regionalization, involves the systematic identification of TFs, and the regulatory elements and genes downstream of TFs. Currently, the regional-specification functions of a few TFs in embryonic cortical progenitors are known, and little is known about their direct transcription targets, the nature of the regulatory elements that these TFs control, and the transcriptional circuitry that integrates development and function of these cells. Here we propose to make inroads into each of these components of the TF hierarchy regulating cortical development. Furthermore, we aim to elucidate transcriptional mechanisms through which patterning of cortical progenitors is transmitted to, and maintained in, cortical neurons. We hypothesize that enhancers active in the ventricular zone, subventricular zone and the cortical plate are differentially bound by TFs that drive expression of region/layer-specific genes in post-mitotic cortical neurons. The enhancers serve as protein-binding modules that translate rostrocaudal gradients of TFs in cortical progenitors into region-specific expression in cortical neurons. Herein we focus on the transcriptional mechanisms controlling the generation of different regions of the cerebral cortex (cortical regionalization). The Five Specific Aims extend upon our earlier work on regionalization of cortical progenitors by FGF-signaling, TFs and enhancer elements. Here we investigate transcriptional regulation of cortical patterning by defining the TFs, and other genes, that are regulated by COUPTF1, EMX2, and PAX6 (Aim 1). We then use chromatin immunoprecipitation-DNA sequencing (ChIP-Seq) to define the regulatory element (RE) and gene targets of COUPTF1, EMX2, and PAX6 (Aim 2). Next, we use fluorescent activated cell sorting (FACS) to purify cells from the VZ, SVZ, CP and layers 5&6 to elucidate the epigenomic states of REs (and genes) using Histone ChIP-Seq. This will help us understand the molecular mechanisms that transmit regional patterning information from cortical progenitors to neurons (Aim 3). Finally, we define the function of REs related to cortical patterning using transgenic mice to assess RE activity (Aims 4) and REs deletions to define their role in gene regulation (Aim 5). Once integrated with human genetic information, this will enable us to gain powerful insights into how abnormalities in specific gene networks cause human neuropsychiatric disorders.