NUCLEAR INTEGRATION OF ENDOTHELIAL SIGNALS

内皮信号的核整合

• 批准号: 6602440
• 负责人: Tucker O Collins
• 金额: $ 6.87万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6602440
• 关键词: cAMP response element binding protein; calcium binding protein; gel mobility shift assay; gene induction /repression; genetic promoter element; genetic regulation; genetic transcription; genetically modified animals; human tissue; immunocytochemistry; intermolecular interaction; laboratory mouse; leukocyte adhesion molecules; nuclear factor kappa beta; phosphoprotein phosphatase; selectins; tissue /cell culture; transcription factor; transfection; vascular endothelium

Expression of endothelial-leukocyte adhesion molecule is dramatically induced by inflammatory cytokines. This increased expression occurs at the transcriptional level and requires activation of the nuclear factor-kappaB (NF-kB) system. Recent studies indicate that the p65 component of NF-kB, like many signal dependent transcriptional activators, interacts with the transcriptional co-activator CREB-binding protein (CBP). In this continuing project, we will investigate whether CBP is part of a novel level of nuclear regulation linking diverse signaling systems in endothelial cells and test the hypothesis that competition for limiting amounts of CBP facilitates the activation of some signal dependent genes at the expense of others. In the renewal period we propose to determine if this regulatory system is relevant to the process of endothelial activation during inflammatory responses. In Specific Aim #1, the antagonistic interactions between p65 and other signal-dependent transcription factors occur because for limiting amounts of the common transcriptional co-activator, CBP. These studies will examine the levels of CBP expression in quiescent and cytokine-activated cultured endothelial cells, determine if levels of the co-activator limit NF-kappaB dependent gene expression, and will explore the molecular basis of the antagonistic interaction. In Specific Aim #2, the pathophysiologic consequences of CBP over- expression in endothelial cells will be examined in a transgenic model of endothelial activation. In this defined genetic context, we will determine if CBP over expression increases induction of NF-kappaB dependent genes and diminishes the negative regulatory effects of the activated nuclear receptors on the induction of kappaB-dependent genes. Like the induction process, decreased expression of the endothelial adhesion molecules following cytokine exposure is an active process that occurs at the transcriptional level. This level of negative regulation my be key in preventing inappropriate or prolonged expression of some adhesion molecule genes. In Specific Aim #3, the mechanisms responsible for the post-induction transcriptional repression of E-selectin will continue to be investigated. These studies will determine the role of the dual specificity phosphatases in limiting the expression of this adhesion molecule gene using tools developed in this project, as well as unique cellular and animal reagents developed by collaborators. Collectively, the findings from these studies should provide insights into two new endothelial regulatory systems: first, they should indicate if CBP serves an integration function for interactions between p65 and other classes of CBP dependent transcription factors during cytokine-induced gene expression; and second, they should define the mechanisms which tightly control the post-induction transcriptional repression of the E- selectin gene.

内皮 - 白细胞粘附分子的表达急剧 由炎症细胞因子诱导。这种增加的表达发生在 转录水平，需要激活核因子-kappab （NF-KB）系统。最近的研究表明，NF-KB的p65成分， 像许多信号依赖性转录激活器一样，与 转录共激活器CREB结合蛋白（CBP）。在这个 继续项目，我们将调查CBP是否是小说的一部分 核调节的水平，将各种信号系统连接 内皮细胞并检验以下假设：竞争限制 CBP量有助于某些信号依赖基因的激活 以牺牲他人为代价。在续签期间，我们建议确定是否 该监管系统与内皮的过程有关 炎症反应期间的激活。 在特定的目标＃1中，p65与其他的拮抗相互作用 信号依赖性转录因子发生，因为限制量 常见的转录共激活因子CBP。这些研究会 检查静态和细胞因子激活中CBP表达的水平 培养的内皮细胞，确定共激活器极限的水平是否 NF-kappab依赖基因表达，将探索分子基础 拮抗相互作用。 在特定的目标＃2中，CBP过度的病理生理后果 内皮细胞中的表达将在一个转基因模型中检查 内皮激活。在这种定义的遗传环境中，我们将确定 如果CBP过度表达增加NF-kappab依赖基因的诱导 并减少活化核的负调节作用 诱导kappab依赖性基因的受体。 像诱导过程一样，内皮表达降低 细胞因子暴露后的粘附分子是一个活跃过程 发生在转录级别。我的负面调节水平 是防止某些不适当或长时间表达的关键 粘附分子基因。 在特定的目标＃3中，负责后诱导的机制 E-选择素的转录抑制作用将继续研究。 这些研究将确定双重特异性磷酸酶的作用 使用工具限制该粘附分子基因的表达 在该项目以及独特的细胞和动物试剂中开发 由合作者开发。 总的来说，这些研究的发现应提供有关 两个新的内皮调节系统：首先，它们应指示CBP是否 为p65与其他的相互作用提供集成函数 细胞因子诱导期间CBP依赖转录因子的类别类别 基因表达；其次，他们应该定义机制 严格控制E-的诱导后转录抑制 选择素基因。