BRWD1 and the molecular regulation of humoral immunity

BRWD1与体液免疫的分子调节

• 批准号: 9899728
• 负责人: Domenick Edward Kennedy
• 金额: $ 3.37万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-12-01 至 2020-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9899728
• 关键词: Affect; Affinity; Alleles; Antibodies; Antigens; Applications Grants; Attenuated; Autoimmunity; B-Cell Development; B-Lymphocyte Subsets; B-Lymphocytes; BCL6 gene; Binding Sites; Bone Marrow; Cells; Chromatin; Coupled; Data; Defect; Development; Disease; Enhancers; Ensure; Ephrin-A5; Epigenetic Process; Exhibits; Fellowship; Generations; Genes; Genetic; Genetic Recombination; Genetic Transcription; Genome; Heterogeneity; Histones; Human; Humoral Immunities; IRF4 gene; Immune response; Immunity; Immunization; Immunize; Immunoglobulin Somatic Hypermutation; Immunologic Deficiency Syndromes; Immunologics; Impairment; Individual; Infection; Knowledge; Laboratories; Light; Malignant Neoplasms; Mediating; Memory B-Lymphocyte; Mentorship; Modeling; Molecular; Mus; Mutation; Nucleosomes; Patients; Plasmablast; Population; Positioning Attribute; Proliferating; Reader; Regulation; Reporting; Research; Role; Scientist; Sorting - Cell Movement; Structure of germinal center of lymph node; Testing; Therapeutic; Training; Transcriptional Regulation; WD Repeat; adaptive immunity; base; cell growth regulation; design; differential expression; epigenetic regulation; experimental study; hypogammaglobulinemia; insight; lymph nodes; novel; plasma cell development; programs; response; single-cell RNA sequencing; transcription factor

PROJECT SUMMARY Our laboratory recently demonstrated that the lineage-restricted BROMO and WD40 domain containing epigenetic reader BRWD1 opens Igκ and enables assembly of RAG proteins at Jκ. I now report that BRWD1 has a much broader role in late B cell development. In the bone marrow, BRWD1 reshaped chromatin landscape by closing enhancers of genes expressed early in B cell development and opening those of genes expressed in late stages. In the absence of BRWD1, over 7000 genes were aberrantly expressed. While many of these genes are normally expressed in earlier developmental stages, many are also part of the germinal center (GC) transcription program. BRWD1 is first expressed in small pre-B cells. However, Brwd1 expression was much higher in naïve follicular (FO) and highest in day 12 GC B cells. These data suggest BRWD1 could also regulate GC B cell programs. My data in WT GC B cells highly supports this. By using a novel 3- population gating strategy to isolate dark zone (DZ), light zone (LZ), and newly identified population grey zone (GZ), I found large transcriptional and genome accessibility differences between DZ and LZ cells. The GZ is also unique from DZ and LZ B cells based on transcription and genome accessibility, suggesting it may contain a novel GC B cell subpopulation(s). In LZ cells, BRWD1 is expressed in Myc- cells, a transcription factor repressed by BRWD1. Finally, analysis of genes differentially expressed in GC DZ and LZ, compared to those differentially regulated by BRWD1 in small pre-B cells, predicted that BRWD1 represses the DZ program and induces the LZ program. This has immunological implications as immunized mice lacking BRWD1 in GC B cells exhibited disorganized GCs and severely impaired affinity maturation. Overall, these data suggest similarities between genetic programs that separate proliferation and Igκ recombination in development and those that segregate proliferation from selection in GCs. Based on these findings, I hypothesize that by regulating enhancer accessibility BRWD1 is important to regulate transcriptional programs in novel GC B cell subsets. Additionally, I hypothesize that by repressing DZ and inducing LZ genetic programs, BRWD1 is critical for GC-dependent humoral immunity. These hypotheses will be tested in the following Specific Aims: Aim 1. Define transcriptional regulation of normal germinal center responses. Aim 2. Determine the role of BRWD1 in adaptive immunity.

项目摘要 我们的实验室最近证明，谱系限制的BROMO和WD 40结构域包含 表观遗传阅读器BRWD 1打开IG κ，并使RAG蛋白能够在J κ处组装。我现在报告， 在晚期B细胞发育中具有更广泛的作用。在骨髓中，BRWD 1重塑染色质 通过关闭在B细胞发育早期表达的基因的增强子和打开在B细胞发育早期表达的基因的增强子， 在晚期阶段表达。在没有BRWD 1的情况下，超过7000个基因异常表达。虽然许多 这些基因通常在早期发育阶段表达，许多也是germ的一部分。 中心（GC）转录程序。BRWD 1首先在小的前B细胞中表达。然而，Brwd 1表达 在幼稚滤泡（FO）中要高得多，在第12天的GC B细胞中最高。这些数据表明BRWD 1可以 也调节GC B细胞程序。我在WT GC B细胞中的数据高度支持这一点。通过使用一个新的3- 群体门控策略，以隔离暗区（DZ）、亮区（LZ）和新识别的群体灰色区 (GZ)，我发现DZ和LZ细胞之间存在较大的转录和基因组可及性差异。广州是 基于转录和基因组可及性，它与DZ和LZ B细胞也是独特的，这表明它可能含有 新的GC B细胞亚群。在LZ细胞中，BRWD 1在Myc细胞中表达，Myc细胞是一种转录因子， 被BRWD 1抑制。最后，分析GC DZ和LZ中差异表达的基因， BRWD 1在小前B细胞中的差异调节，预测BRWD 1抑制DZ程序， 启动LZ程序。这具有免疫学意义，因为免疫小鼠在GC B中缺乏BRWD 1 细胞表现出GC紊乱和亲和力成熟严重受损。总的来说，这些数据表明， 在发育中分离增殖和IG κ重组的遗传程序之间的相似性， 那些在GC中将增殖与选择分离的基因。基于这些发现，我假设， 调节增强子可及性BRWD 1对调节新型GC B细胞中的转录程序是重要的 子集此外，我假设通过抑制DZ和诱导LZ遗传程序，BRWD 1是关键的 GC依赖的体液免疫。这些假设将在以下具体目标中进行检验： 目标1.定义正常生发中心反应的转录调控。 目标二。确定BRWD 1在获得性免疫中的作用。