Molecular Basis of the Selective Assembly of Functionally Distinct PRC1s

功能不同的 PRC1 选择性组装的分子基础

• 批准号: 10515114
• 负责人: CHONGWOO A KIM
• 金额: $ 45万
• 依托单位: MIDWESTERN UNIVERSITY (GLENDALE AZ)
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-22 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10515114
• 关键词: Affect; Affinity; Architecture; Automobile Driving; Binding; Biological Assay; Cells; Chromatin; Complex; DNA; Data; Disease; Drosophila genus; Ensure; Epigenetic Process; Evolution; Family; Fluorescence Resonance Energy Transfer; Gene Expression Regulation; Genetic Materials; Genome; Genomic approach; Homologous Gene; Housing; Human; Interferometry; Lead; Malignant Neoplasms; Measures; Mediating; Molecular; Molecular Machines; Names; PRC1 Protein; Polycomb; Polymers; Proteins; Publishing; Regulation; Regulator Genes; Role; SAM Domain; Secondary to; Series; Stem cell pluripotency; Structure; System; Testing; Therapeutic; Ubiquitination; Variant; Work; X-Ray Crystallography; analytical ultracentrifugation; base; biophysical techniques; cancer cell; drug development; histone modification; interest; malformation; member; novel; paralogous gene; polymerization; protein protein interaction; stem; stem cell proliferation; ubiquitin-protein ligase

PROJECT SUMMARY/ABSTRACT PROBLEM: Polycomb repressive complex 1 (PRC1) is a multi-protein assembly that epigenetically regulates chromatin, which when misregulated, results in cancer. Originally identified in Drosophila as a four-component complex, PRC1 has expanded its membership and functional repertoire over evolution. An important unanswered question concerning human PRC1 is how certain combinations of PRC1 proteins assemble while others do not, and how the types of PRC1s formed change during cellular differentiation. PRC1 assembly is currently understood to occur through a series of 1:1 protein-protein interactions. This view, unfortunately, does not explain how the protein-protein interaction of one PRC1 domain can somehow influence the binding selectivity of another, seemingly unrelated protein-protein interaction. We have identified novel interactions secondary to the known 1:1 direct interactions that provide selective checkpoints for including specific protein combinations thereby allowing selective PRC1 assemblies. OBJECTIVE: We will systematically characterize these secondary protein-protein interactions then investigate its role in the assembly and function of the distinct PRC1s. METHODS: We will use biophysical methods (X-ray crystallography, analytical ultracentrifugation, biolayer interferometry) to dissect the molecular basis of these selective assemblies. The functional consequences of the secondary interactions that form these assemblies will be assessed using a novel FRET- based histone modification assay. SIGNIFICANCE: Gene regulation is performed by many different proteins, all of which work within multi-component systems. Current genomic approaches to investigating gene regulation, while informative, lack a molecular perspective of protein-protein interactions necessary for a complete understanding of these systems. We propose to fill this gap by determining how specific PRC1s assemble and function. By defining the molecular choreography underlying PRC1 assembly, we will provide a new perspective on the regulation and function of these complexes in genome regulation. Our results may also be broadly applicable for understanding other gene regulatory systems, many of which utilize multi- component systems with different homolog combinations.

项目总结/摘要 问题：Polycomb repressive complex 1（PRC 1）是一种多蛋白组装体， 染色质，当调控不当，导致癌症。最初在果蝇中被鉴定为四种成分 复杂，PRC 1已经扩大了其成员和功能的演变。一个重要 关于人类PRC 1的未解问题是PRC 1蛋白的某些组合如何组装， 其他人没有，以及PRC 1的类型如何在细胞分化过程中发生变化。PRC 1组件是 目前理解为通过一系列1：1蛋白质-蛋白质相互作用发生。不幸的是， 不能解释一个PRC 1结构域的蛋白-蛋白相互作用如何以某种方式影响结合 另一个看似无关的蛋白质-蛋白质相互作用的选择性。我们已经发现了新的相互作用 其次是已知的1：1直接相互作用，其为包括特定蛋白质提供选择性检查点 组合，从而允许选择性PRC 1组装。目标：我们将系统地表征 这些次级蛋白质-蛋白质相互作用然后研究其在不同的蛋白质的组装和功能中的作用。 PRC1。方法：我们将使用生物物理学方法（X射线晶体学，分析超离心， 生物层干涉测量法）来剖析这些选择性组装的分子基础。功能 形成这些组件的次级相互作用的后果将使用新的FRET进行评估， 基于组蛋白修饰的测定。意义：基因调控是由许多不同的蛋白质， 所有这些都在多组件系统中工作。研究基因的基因组学方法 调控，虽然信息，缺乏必要的蛋白质-蛋白质相互作用的分子视角， 全面了解这些系统。我们建议通过确定特定PRC 1 组装和功能。通过定义PRC 1组装背后的分子编排，我们将提供一个 关于这些复合物在基因组调节中的调节和功能的新视角。我们的研究结果可能 也可广泛应用于理解其他基因调控系统，其中许多利用多- 具有不同同系物组合的组分系统。