Trib1 in NF-kappaB Signaling: Insights into MALT1 Regulation and Leukemia

NF-kappaB 信号传导中的 Trib1：深入了解 MALT1 调节和白血病

• 批准号: 9110909
• 负责人: Kelly Rome
• 金额: $ 3.03万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9110909
• 关键词: A20 protein; Acute Myelocytic Leukemia; Apoptosis; Binding; Biological Assay; Bone Marrow; Cell Proliferation; Cell Survival; Cell physiology; Cells; Collaborations; Data; Dependence; Development; Developmental Process; Diagnosis; Disease; Drosophila genus; Genetic; Health; Hematologic Neoplasms; Hematopoietic; Homologous Gene; Human; Knowledge; Leukemic Cell; Link; Lymphocyte; Maintenance; Maps; Mediating; Mediator of activation protein; Monoubiquitination; Mucosa- associated lymphoid tissue lymphoma translocation protein-1; Mus; Myelogenous; NF-kappa B; Oncogenes; Oncogenic; Pathogenesis; Pathway interactions; Patients; Peptide Hydrolases; Phosphorylation; Polyubiquitination; Proteins; Publishing; Regulation; Reporter; Role; Sampling; Signal Transduction; Small Interfering RNA; Specificity; Structural Biologist; Structure; Therapeutic; Therapeutic Intervention; Ubiquitin; Ubiquitination; Universities; Wild Type Mouse; Work; cell motility; improved; inhibitor/antagonist; insight; knock-down; leukemia; leukemia treatment; mouse model; mutant; novel; outcome forecast; overexpression; patient subsets; progenitor; protein function; reconstitution; research study; retroviral transduction; scaffold; small molecule inhibitor; targeted treatment; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): Through the proposed work, I will characterize the role of Tribbles homolog 1 (Trib1) in NF-κB signaling, and identify the implications of this role in the pathogenesis of Acute Myeloid Leukemia (AML). We identified MALT1 as a Trib1interacting protein in a screen to identify novel Trib binding partners. Trib1 overexpression in the Jurkat Tcell line enhanced NF-κB activity in a NF-κB-responsive reporter assay. Given the function of MALT1 in mediating NF-κB signaling, I hypothesize that Trib1 enhances NF-κB activation by regulating MALT1 activity. Published work from my lab identified Trib1 as an oncogene in AML. Retroviral transduction of Trib1 in bone marrow progenitors induces AML in reconstituted mice. Furthermore, Trib1 is highly expressed in multiple human AML patient subsets. I hypothesize that Trib1 promotes AML pathogenesis by enhancing activation of proinflammatory NF-κB signaling. In Aim 1, I will assess the role of the Trib1:MALT1 interaction in Trib1 regulation of NF-κB. I will first link Trib1 to the MALT1-mediated NF-κB pathway by examining the ability of Trib1 to enhance signaling in the context of MALT1 knockdown or MALT1 deficiency. Furthermore, I will assess the ability of Trib1 to potentiate MALT1induced activation of NF-κB independently of stimulation. To confirm the role of the Trib1:MALT1 interaction in Trib1-mediated NF-κB regulation, I will generate a binding mutant of Trib1 that maintains structural integrity but abrogates the ability to bind MALT1. Both MALT1 scaffolding and protease function are regulated by ubiquitination. Given the association of Trib1 with E3 ubiquitin ligases, I hypothesize that Trib1 enhances MALT1 activity by regulating the ubiquitination status of MALT1. I will use tagged wildtype and mutant ubiquitin constructs to identify the effect of Trib1 on MALT1 ubiquitination. In Aim 2, I will determine the role of NF-κB i Trib1-mediated AML. I will first assess NF-κB activity in Trib1-mediated mouse leukemic cells, as well as in human AML samples selected for high Trib1 expression. To determine the dependence of these leukemic cells on NF-κB, I will treat cells with NF-κB inhibitors and examine cell survival, selfrenewal, proliferation and apoptosis. I will further assess the effect of NF-κB inhibition on both induction and maintenance of Trib1-mediated AML in our mouse model. I will determine the role of the Trib1:MALT1 interaction in AML by analyzing AML induction in the context of MALT1 deficiency/inhibition or by the Trib1 binding mutant developed in Aim 1. This work will provide critical insight into the pathogenesis of AML and may identify novel targets for therapeutic intervention.

描述（由申请人提供）：通过提议的工作，我将描述tribles同源物1 （Trib1）在NF-κB信号传导中的作用，并确定该作用在急性髓性白血病（AML）发病机制中的意义。我们在筛选中发现MALT1是trib1相互作用蛋白，以鉴定新的Trib结合伙伴。在一项NF-κB应答性报告试验中，Jurkat t细胞系中Trib1的过表达增强了NF-κB活性。鉴于MALT1介导NF-κB信号转导的功能，我假设Trib1通过调节MALT1活性来增强NF-κB的激活。我的实验室发表的研究发现，Trib1是AML的一个致癌基因。骨髓祖细胞中Trib1的逆转录病毒转导可诱导重组小鼠的AML。此外，Trib1在多个人类AML患者亚群中高度表达。我假设Trib1通过增强促炎NF-κB信号的激活来促进AML的发病机制。在Aim 1中，我将评估Trib1:MALT1相互作用在Trib1调节NF-κB中的作用。我将首先通过检查Trib1在MALT1敲低或MALT1缺乏的情况下增强信号传导的能力，将Trib1与MALT1介导的NF-κB途径联系起来。此外，我将评估Trib1独立于刺激增强malt1诱导的NF-κB活化的能力。为了确认Trib1:MALT1相互作用在