Uncovering the Role of the DEAD Box Helicase Ddx41 in Hematopoiesis

揭示 DEAD Box 解旋酶 Ddx41 在造血中的作用

• 批准号: 10212445
• 负责人: Joshua Weinreb
• 金额: $ 5.1万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-16 至 2022-07-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10212445
• 关键词: AML/MDS; Acute Myelocytic Leukemia; Address; Affect; Anemia; Animal Model; Blood; Blood Cells; Cell Line; Cells; Clinical; Co-Immunoprecipitations; Complex; Data; Defect; Development; Developmental Biology; Disease; Dysmyelopoietic Syndromes; Elderly; Embryo; Erythropoiesis; Event; Functional disorder; Genes; Genetic; Germ-Line Mutation; Goals; Hematologic Neoplasms; Hematological Disease; Hematology; Hematopoiesis; Hematopoietic; Hematopoietic System; Hematopoietic stem cells; High-Throughput Nucleotide Sequencing; In Situ Hybridization; Lead; Mediating; Messenger RNA; Modeling; Molecular; Molecular Biology Techniques; Mutate; Mutation; Myelopoiesis; Neutropenia; Outcome; Pancytopenia; Pathogenesis; Pathway interactions; Patients; Phenotype; Population; Process; Proteins; RNA Splicing; Regulation; Role; Sampling; Somatic Mutation; Spliceosomes; Stains; Structure; Techniques; Testing; Training; Transgenic Organisms; Work; Zebrafish; advanced disease; bone marrow failure syndrome; cell growth; cell type; cytopenia; experimental study; helicase; in vivo; in vivo Model; insight; knock-down; leukemogenesis; loss of function; mutant; neoplastic cell; novel; novel therapeutic intervention; premalignant

Abstract Myelodysplastic syndromes (MDS), a group of pre-malignant bone marrow failure syndromes arising from defects in hematopoietic stem cells (HSCs), are amongst the most common hematological malignancies of the elderly with ~30% progressing to acute myeloid leukemia (AML). Recently, loss-of-function germline and somatic mutations in the DEAD-box Helicase 41 gene (DDX41) have been identified in patients with MDS and AML, and are thought to contribute to disease pathogenesis. Both germline and somatic DDX41 mutations are thought to promote hematopoietic deregulation and leukemogenesis. Although a strong clinical correlation is found between mutations in DDX41 and MDS, the in vivo role of DDX41 in hematopoiesis has not been elucidated. To address this question, we will characterize hematopoiesis in a zebrafish ddx41 loss-of-function mutant. Our preliminary studies indicate that ddx41 mutants develop neutropenia and anemia. This animal model will allow us to elucidate the in vivo role of Ddx41 in normal hematopoiesis and the underlying mechanism for any defects. DDX41 has been implicated in splicing and shown to associate with components of the spliceosome including Splicing Factor 3B, subunit 1 (SF3B1), the most commonly mutated splicing factor in MDS. Additionally, MDS/AML patient samples with DDX41 mutations displayed errors in mRNA splicing that typically occur when components of the spliceosome are defective. Although these data point towards a role for DDX41 in splicing, it is still unknown if splicing aberrations contribute to the observed abnormalities in DDX41-mutated hematologic diseases. Using ddx41-deficient zebrafish will permit us to delineate the functionally relevant early molecular events leading to blood cell defects when ddx41 is mutated, which is anticipated to provide novel insight into the origins of MDS. In this proposal, we will use our novel in vivo model of Ddx41-deficiency to test the hypothesis that Ddx41 is critical for normal hematopoiesis via regulation of splicing, and that malfunctioning of this process contributes to the hematological defects seen in DDX41- mutated MDS/AML. In Aim 1, we will determine which blood populations require Ddx41 and which functional domains of Ddx41 are required for healthy hematopoiesis. In Aim 2, we will elucidate connections between DDX41 and SF3B1 using protein and genetic interaction studies. Combined these studies will reveal insights into the pathophysiology of DDX41-mutated MDS/AML.

抽象的 骨髓增生综合征（MDS），这是一组由骨髓骨髓衰竭综合征引起的 造血干细胞（HSC）的缺陷是最常见的血液学恶性肿瘤之一 〜30％的老年人发展为急性髓样白血病（AML）。最近，功能丧失种系和 在MDS和 AML，被认为有助于疾病发病机理。种系和体细胞DDX41突变都是 被认为是促进造血失调和白血病发生的。虽然较强的临床相关性是 在DDX41和MDS中发现的突变之间，DDX41在造血中的体内作用尚未是 阐明。为了解决这个问题，我们将在斑马鱼DDX41中表征造血作用 突变体。我们的初步研究表明，DDX41突变体患有中性粒细胞减少和贫血。这动物 模型将使我们能够阐明DDX41在正常造血和基础中的体内作用 任何缺陷的机制。 DDX41与剪接有关，并显示与组件相关联 包括剪接因子3B，亚基1（SF3B1）的剪接体的剪接体的剪接体，这是最常见的突变剪接因子 在MDS中。此外，具有DDX41突变的MDS/AML患者样品在mRNA剪接中显示出错误 通常，当剪接体的组件有缺陷时发生。尽管这些数据指向角色 对于DDX41，在剪接中，剪接像差是否有助于观察到的异常 DDX41突变的血液学疾病。使用DDX41缺陷斑马鱼将使我们能够描述 功能相关的早期分子事件导致DDX41突变时会导致血细胞缺陷，这是 预计会对MD的起源提供新颖的见解。在此提案中，我们将使用我们的小说在体内 DDX41缺陷的模型测试了DDX41通过调节而对正常造血至关重要的假设 剪接，以及此过程的故障有助于DDX41-中看到的血液缺陷 突变的MDS/AML。在AIM 1中，我们将确定哪些血液种群需要DDX41以及哪些功能性 DDX41的结构域是健康造血的。在AIM 2中，我们将阐明 DDX41和SF3B1使用蛋白质和遗传相互作用研究。这些研究的结合将揭示见解 进入DDX41突变的MDS/AML的病理生理。

项目成果

Clinical and mechanistic insights into the roles of DDX41 in haematological malignancies.

• DOI: 10.1002/1873-3468.14487
• 发表时间: 2022-11
• 期刊: FEBS LETTERS
• 影响因子: 3.5
• 作者: Weinreb, Joshua T.;Bowman, Teresa, V
• 通讯作者: Bowman, Teresa, V