The epigenetic reader BRWD1 in peripheral adaptive immunity

外周适应性免疫中的表观遗传阅读器 BRWD1

基本信息

批准号：
10321252
负责人：
Marcus Ramsay Clark
金额：
$ 48.78万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-10 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10321252
关键词：
3-Dimensional ATAC-seq Affect Affinity Alleles Antibodies Antigens Applications Grants Attenuated Autoimmunity B-Cell Development B-Lymphocytes Binding Binding Sites Bone Marrow Cells ChIP-seq Characteristics Chimera organism Chromatin Chromatin Structure DNA Data Defect Development Enhancers Ephrin-A5 Epigenetic Process Failure Flow Cytometry Follicular Dendritic Cells Gene Expression Profile Gene Expression Regulation Genes Genetic Transcription Genome Heterogeneity Hi-C Histologic Human Humoral Immunities IRF4 gene IgK Immunization Immunize Immunoglobulin Class Switching In Situ Infection Knowledge Light Lymphopoiesis Malignant Neoplasms Molecular Mus Mutation Nucleosomes Patients Pattern Peripheral Phenotype Population Positioning Attribute Reader Regulation Reporting Role Sorting - Cell Movement Structure Structure of germinal center of lymph node T-Lymphocyte Testing Transcriptional Regulation WD Repeat Work adaptive immunity base design differential expression fighting genome-wide hypogammaglobulinemia lymph nodes molecular modeling novel novel therapeutics programs recruit response single-cell RNA sequencing three dimensional structure transcription factor vaccine efficacy

项目摘要

PROJECT SUMMARY Recently, we demonstrated that the lineage-restricted BROMO and WD40 domain containing epigenetic reader BRWD1 opens Igk and induces an epigenetic landscape that enables assembly of RAG proteins at Jk. We now report that BRWD1 has a much broader role in late B cell development. BRWD1 reshapes chromatin landscapes by closing enhancers of genes expressed early in B cell development and opening those of genes expressed in late stages. BRWD1 did not affect the expression of critical transcription factors (TFs). Rather, as demonstrated for IRF4, BRWD1 determines the sites they bind across the genome. BRWD1 differentially regulated over 7000 genes, repressing proliferative and inducing differentiation programs. Notably, BRWD1 coordinately repressed Myc and Myc target genes. Furthermore, in humans, BRWD1 mutations are associated with hypogammaglobulinemia. These data indicate that, in both mice and humans, BRWD1 is a master orchestrator of enhancer accessibility that cooperates with TF networks to drive late B cell development. BRWD1 is first expressed in small pre-B cells. However, Brwd1 expression is higher in naïve follicular (FO) and in germinal center (GC) dark zone (DZ) cells. Analysis of genes differentially expressed in GC DZ and light zone (LZ) cells, compared to those differentially regulated by BRWD1 in small pre-B cells, predicts that BRWD1 represses the DZ program and induces the LZ program. Furthermore, differential genome-wide binding of BRWD1 in DZ and LZ cells suggests different functions in each GC subset. Immunizing Brwd1fl/fl x Aicda (AID)- Cre mice revealed that BRWD1 was required for normal antibody isotype switching and affinity maturation. Histologically, GCs were greatly reduced in both size, and number, and lacked follicular dendritic cells. Therefore, we hypothesize that BRWD1 regulates epigenetic states and enhancer landscapes critical for coordination of DZ and LZ transcriptional programs and GC function. We will test this hypothesis in the following Specific Aims: Aim 1. Determine the transcriptional regulation of normal germinal center responses. Aim 2. Determine the role of BRWD1 in adaptive immunity. Aim 3. Determine the role of BRWD1 in initiating GC responses and in maintaining FO B cell identity. !

项目概要最近，我们证明了含有表观遗传阅读器的谱系限制性 BROMO 和 WD40 结构域 BRWD1 打开 Igk 并诱导表观遗传景观，使 RAG 蛋白能够在 Jk 处组装。报告称 BRWD1 在 B 细胞发育后期具有更广泛的作用，可重塑染色质景观。通过关闭 B 细胞发育早期表达的基因的增强子并打开 B 细胞发育早期表达的基因的增强子正如所证明的，BRWD1 并不影响关键转录因子 (TF) 的表达。对于 IRF4，BRWD1 决定了它们在基因组中受 7000 多个差异调节的位点。值得注意的是，BRWD1 协同抑制了增殖和诱导分化程序。此外，在人类中，BRWD1 突变与 Myc 和 Myc 靶基因相关。这些数据表明，在小鼠和人类中，BRWD1 都是一个主要的协调者。与 TF 网络合作驱动晚期 B 细胞发育的增强子可及性。 BRWD1 首先在小前 B 细胞中表达，然而，Brwd1 在幼稚卵泡 (FO) 中表达较高。以及生发中心 (GC) 暗区 (DZ) 细胞中 GC DZ 和光区差异表达的基因分析。与小前 B 细胞中 BRWD1 差异调节的细胞相比，LZ 细胞预测 BRWD1 抑制 DZ 程序并诱导 LZ 程序此外，差异基因组范围内的结合。 DZ 和 LZ 细胞中的 BRWD1 表明每个 GC 亚群的免疫 Brwd1fl/fl x Aicda (AID)- 具有不同的功能。 Cre 小鼠显示 BRWD1 是正常抗体同种型转换和亲和力成熟所必需的。组织学上，GC 的大小和数量都大大减少，并且缺乏滤泡树突状细胞。我们发现 BRWD1 调节表观遗传状态和增强子景观对于 DZ 的协调至关重要和LZ转录程序和GC功能我们将在以下具体目标中检验这个假设：目标 1. 确定正常生发中心反应的转录调控。目标 2. 确定 BRWD1 在适应性免疫中的作用。目标 3. 确定 BRWD1 在启动 GC 反应和维持 FO B 细胞身份中的作用！