Functional Analysis of Epigenetic Complexes

表观遗传复合物的功能分析

• 批准号: 10594059
• 负责人: ROBERT KINGSTON
• 金额: $ 87.68万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10594059
• 关键词: CHD7 gene; Cell Differentiation process; Cell Lineage; Cell Nucleus; Cells; Chromatin; Chromatin Structure; Complex; DNA; DNA Packaging; Development; Developmental Process; Epigenetic Process; Gene Expression Profile; Gene Expression Regulation; Genes; Genetic Transcription; Human; Laboratories; Location; Mammalian Cell; Methylation; Mutation; Nucleosomes; Organ; Organism; PRC1 Protein; Polycomb; Proteins; Regulation; Regulator Genes; Repression; Role; Structure; Tissues; Work; appendage; cell behavior; cohesin; gene product; member; novel; protein function; zygote

Abstract: For humans to develop properly, the fertilized egg must divide in a manner that generates a body that has the correct organs and appendages in the correct places. Much of this is determined by the proper temporal and spatial regulation of master regulatory genes that guide formation of the differentiated cells that make up organs and appendages. A key aspect of this developmental process is the ability to maintain master regulatory genes in a repressed state in cells where their expression might cause inappropriate cell behavior. Mis-expression of even a single master regulatory gene, such as those encoded in the HOX loci, can result in a cell behaving in a manner incompatible with its body location and tissue type. The Polycomb- Group (PcG) group of genes is largely responsible for maintaining this repression, based upon intensive study over the past 70 years. Maintaining active expression patterns for genes is equally critical for development. A set of genes that maintains activation, called the trithorax- Group (trxG), was isolated via their ability to suppress PcG mutations. This application describes the continuation of our work on understanding the function of the proteins encoded by the PcG and trxG genes. These proteins form several complexes. The PcG complexes PRC1 and PRC2 are each large complexes that contain several PcG gene products. PRC1 is the main `engine' of repression in the Polycomb-Group and is known to interact with chromatin, the structure that packages genes in the nucleus of cells. Chromatin structure can render the enclosed DNA inaccessible to activating factors. A prominent hypothesis is that repression can be generated by generating highly packaged DNA that is no longer able to be transcribed and expressed. We describe approaches to investigate the various mechanisms used by PRC1 to generate packaged chromatin. PRC1 works together with PRC2 to generate repression. PRC2 methylates nucleosomes, the primary packaging unit of chromatin, on residue H3K27, a topic of intensive study in numerous laboratories and companies. We intend to provide novel information by exploring repressive activities of PRC2 that are unrelated to methylation. We will also characterize methylation by PRC2 of a separate protein involved in gene regulation, ElonginA. Finally, we will characterize two separate nucleosome remodeling activities encoded by trxG genes, the mammalian SWI/SNF (BAF) complex and mammalian CHD7. We will explore interactions between SWI/SNF subunits and cohesin, a chromatin organizing activity, and determine how those interactions impact long range interactions in chromatin. We will examine the role for a lncRNA called HERVH in targeting CHD7 activity.

摘要：为了人类的正常发育，受精卵必须以以下方式分裂： 生成一个在正确位置具有正确器官和附肢的身体。大部分都是这样的 由主调控基因的适当时间和空间调控决定 指导构成器官和附属物的分化细胞的形成。一个关键方面 这个发育过程的关键在于在受抑制的状态下维持主调控基因的能力 细胞中的状态，它们的表达可能会导致不适当的细胞行为。错误表达 即使是单个主调控基因，例如 HOX 位点中编码的基因，也可以导致细胞 其行为方式与其身体位置和组织类型不相容。多梳- 基因组（PcG）主要负责维持这种抑制，基于 70年来的深入研究。维持基因的活跃表达模式是 对于发展同样重要。一组保持激活的基因，称为三胸- 组 (trxG) 通过其抑制 PcG 突变的能力而被分离出来。这个应用程序 描述了我们在理解所编码蛋白质的功能方面的继续工作 由 PcG 和 trxG 基因决定。这些蛋白质形成几种复合物。 PcG 复合体 PRC1 PRC2 和 PRC2 都是包含多个 PcG 基因产物的大型复合物。 PRC1为主 多梳群中抑制的“引擎”，已知与染色质相互作用 在细胞核中包装基因的结构。染色质结构可以呈现 封闭的 DNA 无法接触到激活因子。一个突出的假设是镇压可以 通过生成不再能够转录的高度包装的 DNA 来生成 表示。我们描述了研究 PRC1 使用的各种机制的方法 生成包装的染色质。 PRC1 与 PRC2 一起产生镇压。中华人民共和国2 甲基化核小体，染色质的主要包装单元，在残基 H3K27 上，这是一个主题 在众多实验室和公司进行深入研究。我们打算提供新颖的 通过探索与甲基化无关的 PRC2 抑制活动来获取信息。我们 还将表征参与基因调控的单独蛋白质的 PRC2 甲基化， 延长素A.最后，我们将表征编码的两个独立的核小体重塑活动 由 trxG 基因、哺乳动物 SWI/SNF (BAF) 复合体和哺乳动物 CHD7 组成。我们将 探索 SWI/SNF 亚基和粘连蛋白（一种染色质组织活性）之间的相互作用， 并确定这些相互作用如何影响染色质中的长程相互作用。我们将 检查名为 HERVH 的 lncRNA 在靶向 CHD7 活性中的作用。