In vivo analysis of signaling dynamics in the Notch interaction network

Notch 相互作用网络中信号动力学的体内分析

• 批准号: 8300107
• 负责人: Alexey Veraksa
• 金额: $ 10.61万
• 依托单位: UNIVERSITY OF MASSACHUSETTS BOSTON
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8300107
• 关键词: Adverse effects; Affinity; Agonist; Angiotensin II; Anti-Inflammatory Agents; Anti-inflammatory; Aorta; Atherosclerosis; Award; Binding; Biology; Blood Vessels; Boston; Complex; DNA Binding; DNA binding protein B; Dana-Farber Cancer Institute; Dependovirus; Development; Dexamethasone; Endoribonucleases; Genes; Genetic Transcription; Glucocorticoid Receptor; Glucocorticoids; Goals; Growth; Half-Life; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Injury; Location; Mediating; Mediator of activation protein; Messenger RNA; Monocyte Chemoattractant Protein-1; Pathway interactions; Platelet-Derived Growth Factor; Play; Post-Translational Protein Processing; Property; Proteins; RNA; RNA-Binding Proteins; Rattus; Recruitment Activity; Regulation; Role; Signal Pathway; Signal Transduction; Small Interfering RNA; Testing; Vascular Diseases; beta-Chemokines; cytokine; design; endoribonuclease; in vivo; insight; mRNA Stability; mRNA Transcript Degradation; macrophage; mimetics; monocyte; notch protein; novel; programs; receptor binding; response; transcription factor; vascular inflammation

Our program project focuses on vascular inflammation. This project focuses on Monocyte chemoattractant protein-1 (MCP-1), a pro-inflammatory CC chemokine that plays a pivotal role in recruiting monocytes/macrophages to the arterial wall, mediating both early progression of atherosclerosis and response of the arterial wall to injury. We have demonstrated that accumulation of MCP-1 in SMC is mediated in large part by changes in mRNA stability. Growth agonists, such as PDGF and angiotensin II (Ang II), increase MCP-1 mRNA half-life (t1/2) from ¿45 min to >3 hr, whereas glucocorticoids decrease the t1/2 to <15 min. Whereas PDGF and Ang II stabilize numerous mRNAs in SMC, the glucocorticoid Dexamethasone (Dex) selectively destabilizes MCP-1 mRNA. The primary goal of this project is to identify the molecules and mechanisms involved in mediating MCP-1 mRNA stability in SMC. We have made substantial progress during the current term of this award, and have demonstrated that Dex-mediated destabilization of MCP-1 mRNA involves a novel mechanism dependent upon the glucocorticoid receptor (GR). Unlike its more typical role as a transcription factor, the GR appears to be part of a degradative complex that specifically binds MCP-1 mRNA. Using an RNA affinity approach, we have identified Y-box binding protein-1 (YB-1), a multifunctional DNA and RNA binding protein with endoribonuclease properties, as a key component of this complex. We believe that we have identified a novel anti-inflammatory pathway mediated by glucocorticoids/GR that involves degradation of MCP-1 mRNA. This renewal will focus on fully elucidating this pathway. We propose 4 aims: 1) Determine the mechanism by which YB-1 and the GR mediate degradation of MCP-1 mRNA in response to Dex. 2) Identify the domains of the GR involved in regulating MCP-1 mRNA stability. 3) Identify other mediators of inflammation that are regulated in SMC by YB-1- and GR-dependent, Dex-mediated mRNA destabilization. 4) Establish that changes in mRNA stability plays an important role in mediating the effect of Dex on MCP-1 mRNA and protein in vivo. These studies may allow development of agents that mimic the potent anti-inflammatory effects of glucocorticoids without inducing their myriad side effects.

我们的计划项目集中在血管炎症。该项目的重点是单核细胞趋化蛋白-1（MCP-1），一种促炎CC趋化因子，在招募单核细胞/巨噬细胞到动脉壁中起着关键作用，介导动脉粥样硬化的早期进展和动脉壁对损伤的反应。我们已经证明，MCP-1在SMC中的积累在很大程度上是由mRNA稳定性的变化介导的。生长激动剂，如PDGF和血管紧张素II（Ang II），增加MCP-1 mRNA半衰期（t1/2）从<$45分钟到>3小时，而糖皮质激素将t1/2降低到<15分钟。而PDGF和Ang II稳定SMC中的许多mRNA，糖皮质激素地塞米松（Dex）选择性地使MCP-1 mRNA不稳定。本项目的主要目标是确定参与调节SMC中MCP-1 mRNA稳定性的分子和机制。在本奖项的当前期限内，我们取得了实质性进展，并证明了Dex介导的MCP-1 mRNA的不稳定性， 涉及依赖于糖皮质激素受体（GR）的新机制。与其作为转录因子的更典型的作用不同，GR似乎是特异性结合MCP-1 mRNA的降解复合物的一部分。使用RNA亲和的方法，我们已经确定了Y-box结合蛋白-1（YB-1），一个多功能的DNA和RNA结合蛋白与内切核糖核酸酶的性质，作为这个复杂的关键组成部分。我们相信，我们已经确定了一种新的抗炎途径介导的糖皮质激素/GR，涉及MCP-1 mRNA的降解。这次更新将侧重于充分阐明这一途径。我们提出了4个目的：1）确定YB-1和GR介导Dex诱导MCP-1 mRNA降解的机制。2)确定参与调节MCP-1 mRNA稳定性的GR结构域。3)确定在SMC中通过YB-1和GR依赖性、Dex介导的mRNA不稳定调节的其他炎症介质。4)确定mRNA稳定性的变化在介导Dex对体内MCP-1 mRNA和蛋白的影响中起重要作用。这些研究可能允许开发 模拟糖皮质激素的强效抗炎作用，而不诱导其无数的副作用。