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: 8065764
• 负责人: Alexey Veraksa
• 金额: $ 9.83万
• 依托单位: UNIVERSITY OF MASSACHUSETTS BOSTON
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8065764
• 关键词: Adverse effects; Affinity; Agonist; Angiotensin II; Anti-Inflammatory Agents; Anti-inflammatory; Aorta; Atherosclerosis; Award; Binding; Biology; Blood Vessels; Complex; DNA; DNA binding protein B; Dependovirus; Development; Dexamethasone; Endoribonucleases; Figs - dietary; 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.

我们的项目重点是血管炎症。该项目重点研究单核细胞趋化蛋白-1 (MCP-1)，这是一种促炎性 CC 趋化因子，在将单核细胞/巨噬细胞募集至动脉壁、介导动脉粥样硬化的早期进展和动脉壁对损伤的反应方面发挥着关键作用。我们已经证明，MCP-1 在 SMC 中的积累很大程度上是由 mRNA 稳定性的变化介导的。生长激动剂，例如 PDGF 和血管紧张素 II (Ang II)，可增加 MCP-1 mRNA 半衰期 (t1/2) 从 45 分钟缩短至 >3 小时，而糖皮质激素则将 t1/2 缩短至 <15 分钟。 PDGF 和 Ang II 可以稳定 SMC 中的大量 mRNA，而糖皮质激素地塞米松 (Dex) 可以选择性地破坏 MCP-1 mRNA 的稳定性。该项目的主要目标是确定参与介导 SMC 中 MCP-1 mRNA 稳定性的分子和机制。我们在本奖项的当前任期内取得了实质性进展，并证明 Dex 介导的 MCP-1 mRNA 不稳定 涉及依赖糖皮质激素受体（GR）的新机制。与其作为转录因子的更典型作用不同，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 亲和方法，我们确定了 Y-box 结合蛋白-1 (YB-1)，一种具有内切核糖核酸酶特性的多功能 DNA 和 RNA 结合蛋白，是该复合物的关键成分。我们相信我们已经确定了一种由糖皮质激素/GR 介导的新的抗炎途径，该途径涉及 MCP-1 mRNA 的降解。本次更新将重点全面阐明这一途径。我们提出 4 个目标：1) 确定 YB-1 和 GR 介导 MCP-1 mRNA 响应 Dex 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 SMC 中受 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 和蛋白质的影响中发挥重要作用。这些研究可能有助于开发出以下药物： 模仿糖皮质激素的有效抗炎作用，而不引起其多种副作用。