Notch3 signaling in small-artery-diseases

小动脉疾病中的 Notch3 信号传导

• 批准号: 7024809
• 负责人: ANNE JOUTEL
• 金额: $ 17.01万
• 依托单位: NAT'L INST OF HLTH/MED RES INSERM-PARIS
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7024809
• 关键词: alleles; artery; gene mutation; mutant

DESCRIPTION (provided by applicant): Small-vessel-diseases are a leading cause of Vascular Dementia. Our long-term goal is to elucidate the signaling pathways that control the structural and functional integrity of small arteries and understand the connections between these pathways and the development of small-vessel-diseases, as a prerequisite to the development of therapeutics. The research we propose is focused on the Notch3 signaling pathway. Notch signaling is an evolutionary conserved pathway that plays a central role in the development and maturation of most vertebrate organs. We identified Notch3 as the causative gene of CADASIL, an increasingly recognized autosomal dominant form of systemic small-vessel-disease causing stroke and dementia. We previously showed that 1¿) CADASIL patients carry highly stereotyped missense mutations leading to an odd number of cysteine residues within the extracellular domain of Notch3; 2¿) Notch3 expression is largely confined to small arteries and vascular Smooth Muscle Cells (vSMC) and 3¿) Mice expressing an archetypal CADASIL mutation (R90C) targeted in vSMC develop features of the CADASIL arteriopathy. Our specific hypothesis is that appropriate level of Notch3 activity is critical for structural and functional integrity of small arteries by modulating an RBP-JK dependent, Hes/HEY independent pathway. That hypothesis is supported by our recent findings: 1¿) In adult Notch3 null mice, small arteries exhibit structural defects and cerebrovascular reactivity is strongly defective. Notably, Notch3 null and CADASIL phenotypes are very different; 2¿) RBP-JK dependent activity is abolished in arteries of Notch3 null mice but expression level of Hes/HEY genes is unaffected. Here we propose three specific aims to further our understanding of Notch3-dependent small-vessel-diseases and Notch3 signaling and address a major unresolved issue: the extent to which CADASIL mutations impair Notch3 activity. We will construct and analyze Notch3 gain-of-function mutant mice to determine effect of increasing Notch3 activity in small arteries (Aim #1). We will determine the gene expression signature of loss and gain-of-function alleles of Notch3 and identify direct target genes of Notch3 by microarray analysis on isolated small arteries (Aim # 2). We will investigate effect of the archetypal R90C CADASIL mutation on Notch3 wildtype activity in vivo using our Notch3R90C mice, Notch3 null mice as a "rescue" system and transgenic RBP-JK reporter mice (Aim # 3).

描述（由申请人提供）：小血管疾病是血管性痴呆的主要原因，我们的长期目标是阐明控制小动脉结构和功能完整性的信号通路，并了解这些通路与血管之间的联系。作为开发治疗方法的先决条件，我们建议的研究重点是Notch3信号通路，它是一条发挥核心作用的进化保守通路。我们将 Notch3 确定为 CADASIL 的致病基因，CADASIL 是一种越来越多的常染色体显性遗传形式的系统性小血管疾病，可导致中风和痴呆。 ) CADASIL 患者携带高度定型的错义突变，导致 Notch3 胞外域内出现奇数个半胱氨酸残基； ) Notch3 表达主要局限于小动脉和血管平滑肌细胞 (vSMC) 和 3¿ ) 表达针对 vSMC 的原型 CADASIL 突变 (R90C) 的小鼠会出现 CADASIL 动脉病的特征。我们的具体假设是，适当水平的 Notch3 活性通过调节 RBP-JK 依赖性 Hes/ 对小动脉的结构和功能完整性至关重要。嘿，独立途径。我们最近的发现支持了这一假设：1¿ ) 在成年 Notch3 缺失小鼠中，小动脉表现出结构缺陷，脑血管反应性严重缺陷。值得注意的是，Notch3 缺失和 CADASIL 表型非常不同。 ）Notch3 缺失小鼠的动脉中 RBP-JK 依赖性活性被消除，但 Hes/HEY 基因的表达水平不受影响。在这里，我们提出了三个具体目标，以进一步了解 Notch3 依赖性小血管疾病和 Notch3 信号传导并解决一个问题。主要未解决的问题：CADASIL 突变损害 Notch3 活性的程度我们将构建并分析 Notch3 功能获得突变小鼠，以确定在小型小鼠中增加 Notch3 活性的效果。我们将确定 Notch3 功能丧失和获得功能等位基因的基因表达特征，并通过对分离的小动脉进行微阵列分析来鉴定 Notch3 的直接靶基因（目标 #2）。使用我们的 Notch3R90C 小鼠、Notch3 无效小鼠作为“救援”系统和转基因 RBP-JK，对 Notch3 野生型活性进行原型 R90C CADASIL 突变记者小鼠（目标#3）。