Elucidation of the PRC2 interactome in early human neural development

项目摘要 我的研究调查了表观遗传修饰物调节发育的机制。 哺乳动物的大脑。哺乳动物的大脑包含超过1010个神经元，这些神经元共同突触到 执行多种功能，包括但不限于感觉、认知和有意识的思维。这些 大量的细胞都来自相对较小的神经前体细胞池，这些神经前体细胞分裂和 在胚胎发育过程中根据时空线索进行区分。正确发展 而这些细胞的功能需要精确的基因表达控制，这是由两者介导的 转录因子和表观遗传修饰物。虽然转录因子的突变很好 以导致神经发育缺陷为特征，人们对其机制知之甚少 表观遗传修饰基因突变会导致神经发育缺陷。该项目将通过以下方式开始填补这一空白 分析多梳抑制复合体2(PRC2)复合体，一种甲基化的表观遗传修饰物 组蛋白H3的赖氨酸27(H3K27me3)，调节RNA聚合酶II的转录，是 神经前体细胞的形成和功能。具体地说，我的项目将调查PRC2的监管 神经前体细胞增殖分化为神经元时的功能和基因打靶 命运。利用免疫沉淀-质谱仪，我们最近发现了一种新的相互作用 PRC2成分和一个关键的神经发生决定因素，可能在 基因调控。我们将使用多学科方法来确定这一机制的细节 并阐明这些相互作用如何影响PRC2的功能。为了实现这一目标，我们将首先 生物化学鉴定这种分子相互作用所需的蛋白质结构域或氨基酸。接下来，我们 将决定这种神经发生决定因素如何影响PRC2与基因靶点的结合和影响 转录活性。最后，我们将描绘这种互动对自我更新和 神经前体细胞的分化能力。我们的发现将揭示一种 关键的神经发生决定因素与PRC2相互作用，以编程早期所需的基因表达 神经发生。我的研究使用了多种工具来阐明表观遗传修饰物 调节早期神经发育。我研究的长期目标是定义 染色质修饰物和转录回路在发育过程中调节基因表达的作用 并确定这种串扰中的功能障碍如何导致人类出生缺陷和疾病。

Project Summary My research investigates the mechanisms by which epigenetic modifiers regulate the developing mammalian brain. The mammalian brain contains well over 1010 neurons, which synapse together to perform multiple functions including but not limited to sensation, cognition, and conscious thought. These vast numbers of cells all originate from a relatively small pool of neural progenitors, which divide and differentiate in response to spatiotemporal clues during embryonic development. The correct development and function of these cells requires exquisitely accurate gene expression control that is mediated by both transcription factors and epigenetic modifiers. While mutations in transcription factors are well characterized for causing neurodevelopmental defects, little is known about the mechanisms by which epigenetic modifier mutations cause neurodevelopmental defects. This project will begin filling this gap by analyzing the Polycomb Repressive Complex 2 (PRC2) complex, an epigenetic modifier that methylates lysine 27 of histone H3 (H3K27me3), regulates RNA polymerase II transcription, and is necessary for neural progenitor formation and function. Specifically, my project will investigate the regulation of PRC2 function and gene targeting within neural progenitor cells as they proliferate and differentiate to neuronal fates. Using immunoprecipitation-mass spectrometry, we recently identified a novel interaction between a PRC2 component and a key neurogenesis determinant, which likely has a never-discovered function in gene regulation. We will use multidisciplinary approaches to establish the mechanistic details of this interaction and to elucidate how these interactions affect PRC2 function. To achieve this goal, we will first biochemically identify the protein domains or amino acids required for this molecular interaction. Next, we will determine how this neurogenesis determinant affects PRC2 binding to gene targets and influences transcription activities. Finally, we will delineate the effect of this interaction on the self-renewal and differentiation capacity of neural progenitors. Our findings will reveal the molecular mechanism by which a crucial neurogenesis determinant interacts with PRC2 to program gene expression required for early neurogenesis. My research uses multiple tools to elucidate mechanisms by which epigenetic modifiers regulate early neural development. The long-term goal of my studies is to define the cross-talk between chromatin modifiers and transcriptional circuitry in regulating gene expression in developmental contexts and to determine how dysfunction in this cross-talk contributes to human birth defects and diseases.