Notch Function in Vascular Biology and Angiogenesis

血管生物学和血管生成中的Notch功能

• 批准号: 6997848
• 负责人: Jan K. Kitajewski
• 金额: $ 35.92万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6997848
• 关键词: angiogenesis; angiogenesis factor; biological signal transduction; capillary; cell adhesion molecules; cell differentiation; cell growth regulation; embryogenesis; fibroblast growth factor; gene induction /repression; genetic promoter element; genetically modified animals; immunocytochemistry; in situ hybridization; laboratory mouse; ovary; phosphatidylinositol 3 kinase; protein tyrosine kinase; receptor expression; tissue /cell culture; vascular endothelial growth factors; vascular endothelium; vascular smooth muscle

DESCRIPTION (provided by applicant): The Notch pathway is a conserved signaling mechanism that functions to modulate cell-fate decisions. The overall objectives of this proposal are to define roles for Notch in cell-fate determination during vascular development, physiological angiogenesis and maintenance of vasculature. Our general hypothesis is that Notch is critical for arterial-venous, venous-lymphatic development and for physiological angiogenesis. Our general strategy will use a combination of in vitro angiogenesis/lymphangiogenesis assays and mouse modeling to define the consequences of altering Notch activity in endothelial cells. Our preliminary studies using in vitro assays suggest that Notch promotes sprouting and survival of blood endothelial cells but blocks capillary-like cord formation. In Aim I, using in vitro angiogenesis assays, we evaluate signaling mechanisms that function downstream of Notch, with a focus on the PI-3K/Akt and VEGF-C/VEGFR-3 pathways. In Aim II, we evaluate the VEGFR-3 gene as a direct transcriptional target of Notch and explore a role for Notch in lymphangiogenesis by manipulating cultured lymphatic endothelial cells. In Aim III, we use mouse models that activate or inactivate Notch in embryonic vasculature to examine Notch function. We have developed mouse models that conditionally activate Notch signaling in the vasculature to define Notch action at various stages of embryogenesis. Notch activation in embryonic vasculature will be used to evaluate roles for Notch in arterial/venous and venous/lymphatic specification, recruitment of vascular smooth muscle cells, vascular remodeling, and heart development. Notch genes are expressed in adult vasculature but their postnatal function is unknown. In Aim IV, Notch will be conditionally activated in adult vasculature to evaluate function in vascular integrity. In vivo assays will examine whether Notch contributes to, or interferes, with VEGF- or FGF-induced angiogenesis. Finally, Notch function will be studied in the ovary, which has robust physiological angiogenesis during folliculogenesis and corpus luteum formation. Using a hypophysectomized mouse model that allows hormonal induction of ovarian angiogenesis, we will probe Notch function in ovarian vasculature. These mice will be used to define the consequences to ovarian angiogensis when Notch is conditionally activated in ovarian vessels or interfered with using Notch antagonists. Our long-term objective is to understand Notch function in human vascular disorders and during pathological angiogenesis.

描述（由申请人提供）：Notch通路是一种保守的信号传导机制，其功能是调节细胞命运决定。该提案的总体目标是确定Notch在血管发育、生理性血管生成和脉管系统维持过程中的细胞命运决定中的作用。我们的一般假设是，Notch是动脉-静脉，静脉-淋巴发育和生理血管生成的关键。我们的总体策略将使用体外血管生成/淋巴管生成测定和小鼠建模的组合来定义改变内皮细胞中Notch活性的后果。我们使用体外试验的初步研究表明，Notch促进血液内皮细胞的发芽和存活，但阻断毛细血管样索形成。在目的I中，使用体外血管生成测定，我们评估了Notch下游的信号传导机制，重点是PI-3 K/Akt和VEGF-C/VEGFR-3通路。在目的II中，我们评估了VEGFR-3基因作为Notch的直接转录靶点，并通过操纵培养的淋巴管内皮细胞来探索Notch在淋巴管生成中的作用。在目标III中，我们使用在胚胎血管中激活或抑制Notch的小鼠模型来检查Notch功能。我们已经开发了小鼠模型，其在脉管系统中有条件地激活Notch信号传导，以定义Notch在胚胎发生的各个阶段的作用。胚胎血管系统中的Notch激活将用于评价Notch在动脉/静脉和静脉/淋巴特化、血管平滑肌细胞募集、血管重塑和心脏发育中的作用。Notch基因在成人血管系统中表达，但其出生后功能尚不清楚。在Aim IV中，Notch将在成人血管系统中条件性激活，以评价血管完整性的功能。体内测定将检查Notch是否有助于或干扰VEGF或FGF诱导的血管生成。最后，将在卵巢中研究Notch功能，卵巢在卵泡发生和黄体形成期间具有强大的生理性血管生成。使用垂体切除的小鼠模型，允许激素诱导卵巢血管生成，我们将探测卵巢脉管系统中的Notch功能。这些小鼠将用于定义当Notch在卵巢血管中被条件性激活或使用Notch拮抗剂干扰时对卵巢血管生成的后果。我们的长期目标是了解Notch在人类血管疾病和病理性血管生成过程中的功能。