Dissecting the Role Ubiquitin E3 Ligase UBR5 in Lymphomagenesis

剖析泛素 E3 连接酶 UBR5 在淋巴瘤发生中的作用

• 批准号: 10682906
• 负责人: Shannon Buckley
• 金额: $ 41.37万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10682906
• 关键词: Alleles; Alternative Splicing; Antibodies; B-Cell Activation; B-Cell Development; B-Cell Neoplasm; B-Cell NonHodgkins Lymphoma; B-Lymphocyte Subsets; B-Lymphocytes; Blood; C-terminal; CRISPR/Cas technology; Catalytic Domain; Cell Cycle; Cell Maturation; Cell physiology; Cells; Complex; Cysteine; DNA Damage; Data; Defect; Development; Disease; Disease Progression; Evolution; Frameshift Mutation; Future; Genes; Genetic; Genetic Transcription; Goals; Lead; Length; Lymphoid; Lymphoma; Lymphoma cell; Lymphomagenesis; Malignant Neoplasms; Mantle Cell Lymphoma; Mantle Zone; Messenger RNA; Modeling; Molecular; Mus; Mutant Strains Mice; Mutate; Mutation; Non-Hodgkin' s Lymphoma; Nonsense Codon; Pathogenesis; Pathway interactions; Patients; Phenotype; Plasma Cells; Population; Protein Splicing; Proteins; Proteomics; Publishing; RNA Splicing; Role; Sampling; Signal Transduction; Spleen; Spliceosomes; Structure of germinal center of lymph node; Survival Rate; System; Technology; Testing; Therapeutic; Therapeutic Agents; Therapeutic Intervention; Ubiquitin; Up-Regulation; base; cohort; conditional mutant; drug discovery; effective therapy; functional disability; insight; knock-down; lymph nodes; migration; mouse model; multicatalytic endopeptidase complex; mutant; new therapeutic target; next generation sequencing; novel; overexpression; protein degradation; protein expression; scaffold; therapeutic target; tool; tumor; ubiquitin-protein ligase

ABSTRACT Mantle cell lymphoma (MCL) is a rare and aggressive non-Hodgkin’s lymphoma. Unfortunately limited therapies for MCL are currently available suggesting a need to further unravel molecular mechanisms regulating transformation and progression of the disease. The majority of MCL patients have a t(11;14) translocation leading to overexpression of CyclinD1 resulting in extensive proliferation and block in differentiation originating in the mantle zone of the lymph node, however additional mutations are necessary for transformation. Next generation sequencing has identified a number of novel mutations in MCL patients including the ubiquitin E3 ligase UBR5. E3 ubiquitin ligases serve as the substrate-recognizing component for protein degradation by the ubiquitin proteasome system. In a cohort of 196 MCL patients UBR5 was the 3rd most frequently mutated gene and ~60% of the mutations were found within the HECT domain of UBR5, which can accept and transfer ubiquitin molecules to the substrate. In order to understand the role of UBR5 HECT domain in B-lymphoid development we generated a conditional mouse using novel CRISPR/Cas 9 technology. Loss of the HECT domain leads to a block in pre-germinal center B cells in the spleen with a reduction of both B1 and marginal B cell subsets. In addition, follicular B cells in the spleen are phenotypically abnormal and fail to terminally differentiate to anti-body secreting plasma cells. Proteomic studies reveal up-regulation of proteins associated with mRNA splicing via the spliceosome in B cells lacking the HECT domain of UBR5. These studies suggest that 1) cooperation of UBR5 mutations along with expression of cyclinD1 may led to disease progression of mantle cell lymphoma (Aim 1), 2) understanding molecular mechanism of UBR5 mutations could provide potential therapeutic targets in MCL (Aim 2), and 3) aberrant expression of U5 spliceosome proteins block B cell maturation and promote lymphomagenesis (Aim 3). In this application we propose studies to understand the role of UBR5 and its interacting proteins in B-cell lymphomagenesis and define molecular pathways regulated by UBR5 in B-cells. Our goal of the proposed studies is to provide insights to mantle cell lymphoma transformation, progression and potential future therapeutics targets.

抽象的 地幔细胞淋巴瘤（MCL）是一种罕见且具有侵略性的非霍奇金淋巴瘤。不幸的是有限 目前可获得MCL的疗法，这表明需要进一步阐明分子机制 调节疾病的转化和进展。大多数MCL患者有T（11; 14） 易位导致Cyclind1过表达，导致广泛的增殖和阻塞 源自淋巴结的地幔区域的分化，但是需要其他突变 转型。下一代测序已经确定了MCL患者的许多新型突变 包括泛素E3连接酶UBR5。 E3泛素连接酶是底物识别的成分 泛素蛋白质组系统的蛋白质降解。在196个MCL患者的队列中，UBR5是第三名 最常见的突变基因和〜60％的突变是在UBR5的Hect域内发现的， 可以接受并将泛素分子转移到底物。为了了解UBR5 Hect的作用 B淋巴发育中的域，我们使用新型CRISPR/CAS 9技术产生了有条件的小鼠。 Hect结构域的丧失导致脾脏前中心B细胞中的一个阻滞 B1和边缘B细胞子集。此外，脾脏中的卵泡B细胞在表型上异常和失败 最终区分抗体分泌的浆细胞。蛋白质组学研究揭示了蛋白质的上调 与缺乏UBR5的B细胞中的B细胞中的剪接体进行mRNA剪接相关。这些 研究表明，1）UBR5突变的合作以及Cyclind1的表达可能导致疾病 地幔细胞淋巴瘤的进展（AIM 1），2）了解UBR5突变的分子机制 可以在MCL中提供潜在的治疗靶标（AIM 2）和3）U5剪接体的异常表达 蛋白质阻断B细胞成熟并促进淋巴作用（AIM 3）。在此应用中，我们建议研究 了解UBR5及其相互作用蛋白在B细胞淋巴瘤发生中的作用并定义分子 B细胞中由UBR5调节的途径。我们提出的研究的目标是为地幔细胞提供见解 淋巴瘤转化，进展和潜在的未来治疗靶标。