BRWD1 in adaptive humoral immunity

BRWD1在适应性体液免疫中的作用

• 批准号: 9307294
• 负责人: Marcus Ramsay Clark
• 金额: $ 24.19万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-01-18 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9307294
• 关键词: Affinity; Alleles; Antibodies; Antibody Affinity; Antigens; Applications Grants; Area; B-Cell Development; B-Lymphocyte Subsets; B-Lymphocytes; BCL1 Oncogene; Binding Sites; CXCR4 gene; Cell Cycle Arrest; Cells; Chromatin; Competence; Darkness; Data; Development; EZH2 gene; Enhancers; Ensure; Environment; Ephrin-A5; Epigenetic Process; Follicular Dendritic Cells; Genes; Genetic; Genetic Recombination; Genetic Transcription; Histones; Humoral Immunities; IRF4 gene; Immunize; Immunoglobulin Somatic Hypermutation; Immunologics; Infection; Light; Lymphoid; Maintenance; Mediating; Metabolic; Modeling; Mus; Organ; Pathway interactions; Peripheral; Phenotype; Plasma Cells; Population; Proliferating; Reader; Reporting; Reticular Cell; Role; Signal Transduction; Structure; Structure of germinal center of lymph node; T-Lymphocyte; Testing; Transcription Repressor/Corepressor; WD Repeat; XCL1 gene; adaptive immunity; base; differential expression; epigenetic regulation; migration; novel; permissiveness; plasma cell differentiation; programs; promoter; response; segregation; support network; transcription factor; transcriptome sequencing

PROJECT SUMMARY Recently, we demonstrated that the lineage-restricted BROMO and WD40 domain containing epigenetic reader BRWD1 opens Igκ and enables assembly of RAG proteins at Jκ. We now report that BRWD1 has a much broader role in late B cell development. At distances of up to 5 mb from sites of binding, 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 were normally expressed in earlier developmental stages, many were 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. In light zone (LZ) cells, BRWD1 is expressed in Myc- cells, a transcription factor repressed by BRWD1. Finally, analysis of genes differentially expressed in GC dark zone (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. 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, we hypothesize that BRWD1 is required for maintaining FO cell identity. Furthermore, we 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: Derive a conditional allele of Brwd1. Aim 2. Determine role of BRWD1 in maintaining follicular B cell identity. Aim 3. Determine the role of BRWD1 in adaptive immunity.

项目概要 最近，我们证明谱系限制的 BROMO 和 WD40 结构域包含表观遗传 阅读器 BRWD1 打开 Igκ 并能够在 Jκ 处组装 RAG 蛋白。我们现在报告 BRWD1 有一个 BRWD1 在 B 细胞后期发育中发挥更广泛的作用，距离结合位点最多 5 mb。 通过关闭 B 细胞发育早期表达的基因增强子来重塑染色质景观 打开晚期表达的基因，在没有 BRWD1 的情况下，超过 7000 个基因出现异常。 虽然其中许多基因在早期发育阶段正常表达，但许多基因却在早期发育阶段表达。 BRWD1 也是生发中心 (GC) 转录程序的一部分，首先在小前 B 细胞中表达。 然而，Brwd1 的表达在幼稚卵泡 (FO) 中要高得多，并且在光照下第 12 天的 GC B 细胞中表达最高。 BRWD1 在 Myc- 细胞中表达，这是一种被 BRWD1 抑制的转录因子。 分析 GC 暗区 (DZ) 和 LZ 中差异表达的基因，与差异表达的基因进行比较 在小前 B 细胞中受 BRWD1 调节，预测 BRWD1 抑制 DZ 程序并诱导 这些数据表明分离增殖和 Igκ 的遗传程序之间存在相似性。 发育中的重组以及GC中将增殖与选择分离的重组。 研究结果表明，BRWD1 是维持 FO 细胞身份所必需的。 通过抑制 DZ 和诱导 LZ 遗传程序，BRWD1 对于 GC 依赖性体液至关重要 这些假设将在以下具体目标中得到检验： 目标 1：导出 Brwd1 的条件等位基因。 目标 2. 确定 BRWD1 在维持滤泡 B 细胞特性中的作用。 目标 3. 确定 BRWD1 在适应性免疫中的作用。