Interrogating YY1's role in chromatin organization during erythroid cell state transitions

探究 YY1 在红细胞状态转变过程中染色质组织中的作用

• 批准号: 10464524
• 负责人: Jessica Lam
• 金额: $ 3.35万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10464524
• 关键词: 3-Dimensional; Acute; Address; Architecture; Auxins; Binding; Blood; Cell Cycle; Cell Cycle Progression; Cells; ChIP-seq; Chromatin; Chromatin Loop; Chromatin Structure; Congenital Disorders; DNA Polymerase II; Data; Defect; Development; Disease; Distant; Enhancers; Epigenetic Process; Erythroblasts; Erythroid; Erythroid Cells; Erythropoiesis; Etiology; G1 Phase; G1/S Transition; Gene Expression; Genes; Genetic; Genetic Transcription; Genome; Glean; Hematopoiesis; Hi-C; Higher Order Chromatin Structure; Instruction; Interphase; Interphase Cell; Kinetics; Lead; Malignant Neoplasms; Maps; Mediating; Metaphase; Mitosis; Mitotic; Mothers; Phase Transition; Play; Population; Regulation; Resolution; Role; Specificity; Sum; Surveys; System; Tertiary Protein Structure; Testing; Transitional Cell; Work; YY1 Transcription Factor; cell type; cohesin; erythroid differentiation; genomic data; insight; predictive modeling; promoter; recruit; restoration; spatiotemporal; transcription factor

Project Summary Chromatin structure plays an important role in instructing gene expression and maintaining cellular identity. However, much remains unknown regarding how the genome becomes reorganized during crucial transitions, such as cell cycle progression and cellular differentiation. Mitosis is marked by a global cessation of transcription, eviction of transcription factors, and the dissolution of most chromatin structure. During the mitosis to G1 phase transition, newly born cells must therefore address the challenge of rapidly re-establishing 3D genome organization that faithfully reflects that of the mother cell. While CTCF and cohesin-mediated loop extrusion has been shown to forge some chromatin loops, many observed architectural features cannot be explained by this mechanism. Another important architectural factor, YY1, has been implicated in enhancer-promoter loops in studies in interphase cells. However, its dynamics and role in chromatin loop formation has not been explored at the critical juncture between mitosis and G1 phase. We aim to characterize YY1 chromatin occupancy kinetics as it relates to the emergence of chromatin loops. We will test its necessity by interrogating effects of specifically timed depletion during metaphase and during G1 phase entry. We also propose to study the functional importance of YY1- mediated loop formation by characterizing transcriptional changes caused by mitotic depletion. Similarly, the role of YY1 in chromatin organization during hematopoiesis has yet to be clearly defined. YY1 has been proposed to be a regulator of loops essential for development, but previous work has only focused on select loci in limited cell types. To elucidate YY1’s involvement in genome reorganization during developmental transitions, we will characterize YY1 binding and corresponding architectural changes by generating high-resolution Micro-C maps before and after erythroblast maturation. We will also acutely deplete YY1 during differentiation to test its necessity in orchestrating looping reconfiguration in erythroblasts. By utilizing two natural state transitions – cell cycle and erythroid differentiation – as well as an acute degradation system, we aim to gain new insights into the fundamental mechanisms underlying genome organization.

项目摘要 染色质结构在指导基因表达和维持细胞同一性方面起着重要作用。 然而，关于基因组在关键转变期间如何重组， 如细胞周期进程和细胞分化。 有丝分裂的标志是转录的全面停止，转录因子的驱逐，以及细胞分裂。 大多数染色质结构的溶解。在有丝分裂到G1期的转变过程中，新生细胞必须 因此，解决快速重建3D基因组组织的挑战，忠实地反映了 母细胞虽然CTCF和粘附素介导的环挤出已被证明可以形成一些染色质， 循环，许多观察到的建筑特征不能用这种机制来解释。另一个重要 在间期细胞的研究中，结构因子YY 1与增强子-启动子环有关。 然而，其动力学和在染色质环形成中的作用尚未在关键时刻被探索 有丝分裂和G1期之间。我们的目标是表征YY 1染色质占据动力学，因为它与细胞周期有关。 染色质环的出现。我们将通过询问特定时间消耗的影响来测试其必要性 在中期和进入G1期期间。我们还建议研究YY 1的功能重要性- 介导的环的形成，通过表征有丝分裂耗竭引起的转录变化。 同样，YY 1在造血过程中染色质组织中的作用也尚未明确。 YY 1被认为是一个对发展至关重要的循环调节器，但以前的工作只 专注于有限细胞类型中的选择位点。为了阐明YY 1在基因组重组过程中的作用， 发展的过渡，我们将表征YY 1结合和相应的结构变化， 在成红细胞成熟之前和之后产生高分辨率Micro-C图谱。我们还将严重消耗 YY 1的表达，以测试其在成红细胞中协调成环重构的必要性。 通过利用两种自然状态转换-细胞周期和红细胞分化-以及急性 降解系统，我们的目标是获得新的见解的基本机制基因组 organization.