Identification and characterization of chromatin regulators of coordinated synaptic gene expression

项目摘要/摘要 神经系统的功能需要将不同的神经元亚型整合到神经中 引发思想和行为的回路。尽管神经元亚型多种多样，但所有 神经元有共同的关键特征，包括化学突触。目前的模型表明，共享 神经元基因，包括泛突触基因，是由不同的 转录因子在不同神经元亚型中的组合，而亚型特有 突触基因受称为末端选择器的特定转录因子的调节。我们的数据 证明泛神经元和亚型特异性突触基因在时间上是协调的 在突触发生过程中。我们已经确定了一个候选的基因调控网络(GRN) 包括两个已知的先锋因素，并提出了一个模型，在该模型中，积极和消极 染色质可及性调控是突触基因协调调控的基础 表达促进突触形成。在目标1中，我们提出了基因组和体内功能 验证以测试我们的两个候选转录因子，GA富含基序结合模型 因子钳和GagA因子，结合相同的突触基因启动子发挥作用 对染色质的可及性和转录有相反的影响。在目标2中，我们提出了一个 识别协调突触背后的GRN的全面和公正的方法 通过单核RNA-和ATAC-Seq.成功完成这些任务 研究将促进我们对共同神经元特征是如何发展的理解 与细胞命运的获取相协调，并可能通知干细胞的神经元重新编程。

Project Summary/Abstract Nervous system function requires the integration of diverse neuronal subtypes into neural circuits that elicit thought and behavior. Despite the extensive diversity of neuronal subtypes, all neurons share key features, including chemical synapses. Current models indicate that shared neuronal genes, including pan-synaptic genes, are independently regulated by different combinations of transcription factors in distinct neuronal subtypes, whereas subtype-specific synaptic genes are regulated by specific transcription factors called terminal selectors. Our data demonstrate that pan-neuronal and subtype-specific synaptic genes are temporally coordinated during synaptogenesis. We have identified a candidate gene regulatory network (GRN) that includes two known pioneer factors, and propose a model in which positive and negative regulation of chromatin accessibility underlie the coordinated regulation of synaptic gene expression to promote synapse formation. In Aim 1, we propose genomic and in vivo functional validation to test the model that two of our candidate transcription factors, GA-rich motif binding factors CLAMP and GAGA factor, bind to the same promoters of synaptic genes to exert opposite effects on chromatin accessibility and transcription. In Aim 2, we propose a comprehensive and unbiased approach to identifying the GRNs underlying coordinated synaptic gene expression through single-nucleus RNA- and ATAC-Seq. Successful completion of these studies will advance our understanding of how the development of shared neuronal traits is coordinated with cell fate acquisition, and may inform neuronal reprogramming of stem cells.