Defining the role of the BCL7 subunit of mammalian SWI/SNF chromatin remodeling complexes in human cancer

确定哺乳动物 SWI/SNF 染色质重塑复合物的 BCL7 亚基在人类癌症中的作用

• 批准号: 10604291
• 负责人: Kimberlee Hixon
• 金额: $ 4.14万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10604291
• 关键词: ATAC-seq; ATP Hydrolysis; ATP phosphohydrolase; Affect; Amino Acids; Antibodies; Architecture; B cell differentiation; B-Cell Lymphomas; B-Lymphocytes; Binding; Biochemical; Biological Assay; Cell Differentiation process; Cell Line; Cell Maturation; Cell physiology; Cell surface; Cells; Chromatin; Chromatin Remodeling Factor; Chronic Lymphocytic Leukemia; Combinatorics; Complex; Computer Analysis; DNA; Dedications; Development; Disease; Evolution; Family; Gene Expression; Gene Expression Regulation; Generations; Genes; Genetic Transcription; Genomic approach; Genomics; Human; Immune system; Immunoprecipitation; Infection; Knock-out; Length; Link; Lymphoma; Maintenance; Malignant - descriptor; Malignant Neoplasms; Mammalian Cell; Mediating; Multiple Myeloma; Multiprotein Complexes; Mutate; Mutation; N-terminal; Neurodevelopmental Disorder; Nucleosomes; Oncogenic; Organism; Pathogenesis; Physiological Processes; Play; Process; Proliferating; Protein Subunits; Research; Role; SMARCA4 gene; SMARCC1 gene; SWI/SNF Family Complex; Series; Site; Systems Development; Tissues; Transposase; Variant; Western Blotting; cancer subtypes; cell fate specification; chromatin immunoprecipitation; gene product; genome-wide; human disease; large cell Diffuse non-Hodgkin' s lymphoma; nuclease; programs; protein complex; transcriptome sequencing; tumorigenesis; vector; vector control

PROJECT SUMMARY/ABSTRACT The mammalian SWI/SNF (mSWI/SNF) complexes represent a family of ATP-dependent chromatin remodeling complexes (CRCs) that play critical roles in the maintenance of chromatin accessibility and gene expression. Mammalian SWI/SNF complexes are combinatorically assembled from 29 different gene products to generate three distinct 11-15-subunit classes termed BAF, pBAF, and ncBAF complexes. Importantly, mSWI/SNF genes are mutated in over 20% of human cancers, underscoring their critical roles in oncogenesis. While biochemical, structural and genomics-based studies over the past several years have begun to define subunit-specific contributions to overall protein complex function, most subunit functions remain unassigned. BCL7 is a recently- discovered component of all three SWI/SNF complex classes. Despite other mSWI/SNF complex subunits being conserved throughout evolution, BCL7 has only recently emerged in higher-order organisms, suggesting it may be necessary for specialized organismal processes such as mammalian cell differentiation or immune system development. I aim to define the role of the BCL7 subunit in mSWI/SNF complex function in the human cell context. I hypothesize that BCL7 is required for a) SWI/SNF complex biochemical integrity; and b) for genome-wide SWI/SNF targeting and DNA accessibility generation in lymphoma and primary B cells. The role of the mammalian-specific BCL7 subunit in the biochemical composition, targeting, and activity of SWI/SNF complexes remains unknown. First, I aim to determine the impact of BCL7 deletion on SWI/SNF complex biochemical integrity (subunit assembly and stability) and to define the region of BCL7 required for its incorporation into SWI/SNF complexes. BCL7 mutations, including deletions and single-residue substitutions, have been identified primarily in lymphomas and myelomas, cancer subtypes that affect B cell maturation and function. Second, I aim to determine the impact of BCL7 perturbations on the SWI/SNF complex genomic targeting, DNA accessibility generation, and subsequent gene expression in B cell lymphomas such as DLBCL. Third, I aim to determine the functional impact and role of BCL7 in SWI/SNF complex genomic targeting and accessibility generation in healthy human primary B cells. This research will elucidate key features of BCL7-mediated SWI/SNF complex composition, chromatin localization, and resulting DNA accessibility, and gene expression programs in normal and malignant B cells. The mechanisms governing chromatin remodeling complex activities during basic cellular processes and in human disease remain incompletely understood, and with the highly frequent mutations in these processes observed in human cancers, this is a uniquely pertinent and high-impact priority for the field at-large.

项目概要/摘要 哺乳动物 SWI/SNF (mSWI/SNF) 复合物代表了 ATP 依赖性染色质重塑家族 复合物（CRC）在维持染色质可及性和基因表达方面发挥着关键作用。 哺乳动物 SWI/SNF 复合物由 29 种不同的基因产物组合组装而成 三种不同的 11-15 亚基类别，称为 BAF、pBAF 和 ncBAF 复合物。重要的是，mSWI/SNF 基因 在超过 20% 的人类癌症中发生突变，强调了它们在肿瘤发生中的关键作用。在生化的同时， 过去几年基于结构和基因组学的研究已经开始定义亚基特异性 尽管对整体蛋白质复合体功能的贡献，大多数亚基功能仍未分配。 BCL7 是最近- 发现了所有三个 SWI/SNF 复合体类别的组成部分。尽管其他 mSWI/SNF 复合亚基 BCL7 在整个进化过程中都是保守的，最近才在高等生物中出现，这表明它可能 对于特殊的生物过程（例如哺乳动物细胞分化或免疫系统）是必需的 发展。我的目标是确定 BCL7 亚基在人类细胞 mSWI/SNF 复合功能中的作用 语境。 我假设 BCL7 是 a) SWI/SNF 复合体生化完整性所必需的； b) 对于全基因组 淋巴瘤和原代 B 细胞中的 SWI/SNF 靶向和 DNA 可及性生成。的作用 SWI/SNF 复合物的生化组成、靶向和活性中哺乳动物特异性 BCL7 亚基 仍然未知。首先，我的目的是确定 BCL7 缺失对 SWI/SNF 复合物生化的影响 完整性（亚基组装和稳定性）并定义将其纳入所需的 BCL7 区域 SWI/SNF 复合体。已鉴定出 BCL7 突变，包括缺失和单残基取代 主要见于淋巴瘤和骨髓瘤，这些癌症亚型会影响 B 细胞的成熟和功能。二、我的目标 确定 BCL7 扰动对 SWI/SNF 复合体基因组靶向、DNA 可及性的影响 B 细胞淋巴瘤（例如 DLBCL）中的生成和随后的基因表达。第三，我的目标是确定 BCL7 在 SWI/SNF 复杂基因组靶向和可及性生成中的功能影响和作用 健康的人类原代 B 细胞。 这项研究将阐明 BCL7 介导的 SWI/SNF 复合物组成、染色质的关键特征 定位、由此产生的 DNA 可及性以及正常和恶性 B 细胞中的基因表达程序。 在基本细胞过程和过程中控制染色质重塑复杂活动的机制 人类疾病仍未完全了解，并且这些过程中存在高度频繁的突变 在人类癌症中观察到，这对于整个领域来说是一个独特相关且具有高影响力的优先事项。