Treg development and function controlled by cis-regulatory circuits

由顺式调节电路控制的 Treg 发育和功能

• 批准号: 10092894
• 负责人: Ye Zheng
• 金额: $ 64.8万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10092894
• 关键词: 3-Dimensional; Autoimmune Diseases; Autoimmunity; Binding; Biological Assay; Biology; CRISPR/Cas technology; Cell Differentiation process; Cell Lineage; Cell physiology; Cells; Charge; Chromatin Loop; Chromosomes; Collection; Complex; DNA Crosslinking; Data; Data Analyses; Development; Distal; Elements; Enhancers; FOXP3 gene; Gene Expression; Genes; Genetic Screening; Genome; Genomics; Goals; Hi-C; Homeostasis; Human; Immune system; Immunosuppressive Agents; Insulin-Dependent Diabetes Mellitus; Knockout Mice; Lead; Libraries; Link; Lymphocyte Function; Lymphoproliferative Disorders; Maintenance; Malignant Neoplasms; Maps; Methods; Molecular; Multiple Sclerosis; Mus; Mutation; Names; Outcome; Play; Process; Property; Regulatory Element; Regulatory T-Lymphocyte; Research; Research Personnel; Role; Scanning; Side; Signal Transduction; System; T-Lymphocyte Subsets; Techniques; Testing; Therapeutic; anti-tumor immune response; base; design; experience; experimental study; genetic signature; genome-wide; immunopathology; insight; laboratory experiment; loss of function mutation; mutant; novel; novel therapeutics; prevent; promoter; transcription factor; tumor

Project Summary Regulatory T cell (Treg) plays a critical role in maintaining immune system homeostasis and preventing autoimmunity and immunopathology. Compromised Treg function is linked to multiple autoimmune diseases including type 1 diabetes and multiple sclerosis. On the flip side, enrichment of Treg cells within tumors is thought to be a barrier to effective anti-tumor immune response. The development and maintenance of Treg cell lineage are dependent on transcription factor Foxp3, as loss of function mutations lead to severe lymphoproliferative disease in mice and humans. Thus, understanding the mechanisms that govern Foxp3 induction and stability may lead to the development of novel therapies for autoimmune disease and cancer. Previously, Dr. Zheng and colleagues identified three evolutionarily conserved cis-regulatory elements at the Foxp3 locus, which play unique roles in Treg differentiation or maintenance. To expand this line of research, Dr. Zheng’s group will use a CRISPR/Cas9 based approach named CREST-seq (cis-regulatory element scan by tiling-deletion and sequencing) to perform unbiased screen and functional assessment for distal cis-elements near the Foxp3 locus. A preliminary study showed there are potentially up to 50 cis-regulatory elements involved in the control of Foxp3 expression. In-depth characterization of these new cis-elements will advance the understandings on the regulatory circuitry of Foxp3 expression. Numerous studies generated annotations on millions of candidate regulatory elements for thousands of genes in Tregs, but understanding is incomplete on how these elements control their target genes that are kilo-bases or even mega-bases away. Preliminary studies on genome-wide chromosome looping in Tregs generated a collection of distal DNA loops that can potentially regulate Treg signature genes. Furthermore, these data suggest a novel role for Foxp3 in facilitating distal DNA looping. To better understand how cis-regulatory circuitry control Treg differentiation and function, Dr. Zheng’s group will identify and characterize the cis-elements that control Foxp3 expression by a tiling deletion based genetic screen (Aim 1) and explore how distal enhancers regulate gene expression in regulatory T cell through chromosome looping (Aim 2). Furthermore, they will investigate if Foxp3 facilitates chromosome looping to establish and maintain the Treg lineage. Since Treg cell is directly related to autoimmune diseases and cancer, Dr. Zheng’s study will provide insight into the molecular mechanisms of Treg development and function and offer new opportunities to manipulate Tregs for therapeutic purposes.

项目概要 调节性T细胞（Treg）在维持免疫系统稳态和预防疾病方面发挥着关键作用。 自身免疫和免疫病理学。 Treg 功能受损与多种自身免疫性疾病有关 包括 1 型糖尿病和多发性硬化症。另一方面，肿瘤内 Treg 细胞的富集被认为 成为有效抗肿瘤免疫反应的屏障。 Treg细胞谱系的发育和维持 依赖于转录因子 Foxp3，因为功能突变的丧失会导致严重的淋巴增殖 小鼠和人类的疾病。因此，了解控制 Foxp3 诱导和稳定性的机制 可能会导致自身免疫性疾病和癌症的新疗法的开发。此前，郑博士和 同事们在 Foxp3 基因座上发现了三个进化上保守的顺式调控元件，它们发挥着 在 Treg 分化或维持中发挥独特作用。为了扩大这一研究范围，郑博士的团队将使用 基于 CRISPR/Cas9 的方法，名为 CREST-seq（通过平铺删除和顺式调控元件扫描） 测序）对 Foxp3 基因座附近的远端顺式元件进行无偏筛选和功能评估。 初步研究表明可能有多达 50 个顺式调控元件参与 Foxp3 的控制 表达。对这些新顺式元素的深入表征将促进对这些新顺式元素的理解 Foxp3表达的调节电路。大量研究对数百万候选人进行了注释 Tregs 中数千个基因的调控元件，但对这些元件如何发挥作用的了解还不完整 控制距离千碱基甚至兆碱基远的目标基因。全基因组初步研究 Tregs 中的染色体环产生了一组可以潜在调节 Treg 的远端 DNA 环 特征基因。此外，这些数据表明 Foxp3 在促进远端 DNA 环化方面具有新的作用。到 郑博士的团队将更好地了解顺式调节电路如何控制 Treg 分化和功能 通过基于平铺删除的遗传筛选来识别和表征控制 Foxp3 表达的顺式元件 （目标1）并探索远端增强子如何通过染色体调节调节性T细胞中的基因表达 循环（目标 2）。此外，他们将研究 Foxp3 是否促进染色体环的建立和 维持Treg血统。由于Treg细胞与自身免疫性疾病和癌症直接相关，郑博士的研究 研究将深入了解 Treg 发育和功能的分子机制，并提供新的 出于治疗目的操纵 Tregs 的机会。