Cited 2 Action in Cardiac and Neural Development

被引 2 项在心脏和神经发育方面的作用

• 批准号: 6919938
• 负责人: YU-CHUNG YANG
• 金额: $ 38.25万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6919938
• 关键词: RNA interference; apoptosis; cAMP response element binding protein; cardiac myocytes; cardiogenesis; cell population study; chick embryo; coronary vessels; developmental genetics; embryogenesis; gene expression; gene mutation; genetic models; genetically modified animals; hypoxia; hypoxia inducible factor 1; laboratory mouse; model design /development; neural crest; neural plate /tube; neurogenesis; protein binding; protein structure function; transfection /expression vector

DESCRIPTION (provided by applicant): The Cited2 knockout mouse phenotype indicates that Cited2, a recently discovered transcriptional activator, is critical for morphogenesis of the conotruncus (cardiac outflow tract) and the cranial neural tube. Both of these tissues are known to be hypoxic during their development. Cited2 has been shown in in vitro systems to effectively compete with hypoxia-inducible factor 1-alpha (HIF-1alpha) for binding to the CH1 domain of CBP/p300 and to negatively regulate hypoxia-responsive gene expression. Up regulation of hypoxia inducible genes in the Cited2-/- embryo supports this hypothesis. Thus, Cited2 may be especially required for modulating the hypoxia response in those embryonic tissues that experience the lowest oxygen tension during normal development. We will test this hypothesis in mouse and chicken embryos with our main focus on the cardiac outflow tract (OFT). Aim 1: Determine in which cell type or cell types Cited2 expression is required for normal development. We will first determine in detail the expression of the Cited2 protein and mRNA in the embryo at critical stages in heart and neural tube morphogenesis and compare to hypoxic and apoptotic sites. We will specifically knock out Cited2 in the neural crest cells or cardiomyocytes using the Cre-lox system and assay the consequences. Aim 2: Test using in vivo systems the hypothesis that Cited2 is required to compete with HIF-Ia for CBP/p300 binding to down-regulate the hypoxia response in the heart. We will reduce Cited2 action specifically in the cardiomyocytes of the avian OFT and observe the consequences to morphogenesis and the hypoxia response including coronary vascular development. We will cross the Cited2 mice with HIF-Ia mice to determine whether the HIF-Ia gene dosage can modulate Cited2 action and vice versa. These studies will not only provide information critical to our understanding of normal and abnormal heart and neural development but also elucidate the complex interplay between transcription factors and co-factors in vivo.

描述（由申请人提供）：引用的2基因敲除小鼠表型表明，最近发现的转录激活剂CITED2对于Conotruncus（心脏流出道）和颅神经管的形态发生至关重要。这两种组织在发育过程中均为低氧。 Cited2已在体外系统中显示，可以有效地与缺氧诱导因子1-α（HIF-1Alpha）竞争，以与CBP/p300的CH1结构域结合，并对低氧反应性基因表达进行负调节。提高引用的2-/ - 胚胎中缺氧诱导基因的调节支持了这一假设。因此，在正常发育过程中经历最低氧气张力的胚胎组织中调节缺氧反应可能特别需要引用2。我们将在小鼠和鸡胚胎中检验这一假设，主要关注心脏流出区（OFT）。 AIM 1：确定正常发育中需要使用哪种细胞类型或细胞类型2表达。我们将首先详细确定在心脏和神经管形态发生的临界阶段中引用2蛋白和mRNA的表达，并与缺氧和凋亡部位相比。我们将使用CRE-Lox系统在神经rest细胞或心肌细胞中特异性删除引用2，并分析后果。 AIM 2：使用体内系统进行测试。与HIF-IA竞争CBP/p300结合以下调心脏中的缺氧反应，需要使用cusit2的假设。我们将在禽类的心肌细胞中特别减少引用的2作用，并观察到形态发生的后果以及包括冠状动脉血管发育（包括冠状动脉血管发育）的缺氧反应。我们将用HIF-IA小鼠越过引用的2小鼠，以确定HIF-IA基因剂量是否可以调节引用2作用，反之亦然。这些研究不仅为我们对正常和异常心脏和神经发育的理解提供至关重要的信息，而且还阐明了体内转录因子与副因素之间的复杂相互作用。