Identification and Characterization of Genes from del22q

描述（由申请人提供）：Tbx 1是人类、小鼠和斑马鱼心血管发育所必需的。 自从最初认识到该基因在发育中的作用以来，在突变体分析方面取得了相当大的进展，从而提出了新的假设。 Tbx 1是胚胎咽的分割、主动脉弓的形成和心脏流出道的形态发生所需的T-box转录因子。 然而，如果我们不解决两个基本问题，那么关于该基因的进一步知识获取将受到限制：Tbx 1基因调控的关键参与者是什么，以及Tbx 1蛋白的靶点是什么。Tbx 1基因有一个精致的动态调节，在这里，我们表明，这是与胚胎发生过程中的时间特异性作用。例如，心血管发育需要早期表达，而胸腺器官发生和腭发生需要晚期表达。此外，我们还显示了心血管发育过程中Tbx 1功能的组织特异性要求。该提案建立在这些新数据的基础上，以寻找在关键时间和组织中重要的Tbx 1的调节剂和靶标。 总体目标是在Tbx 1发挥作用的遗传途径中建立硬链接。我们相信，这项工作将导致基因引起或修改先天性心脏病。在第一个具体目标中，我们将使用新的方法来鉴定咽内胚层中Tbx 1调节所必需的遗传元件，咽内胚层是Tbx 1功能的关键组织，并且还将确定Tbx 1在该组织中的表达是否足以挽救突变体中观察到的心血管异常。在第二个具体目标中，我们将使用转录组分析和染色质免疫沉淀分析的组合来识别转录靶点。初步数据显示了这种方法的威力。此外，我们建议在体外和体内验证候选靶基因。 该项目直接涉及Tbx 1在心血管发育中的功能，如通过基因的上游调控和相关组织中蛋白质的转录靶点所定义的。数据应提供解剖的遗传网络中断DiGeorge和Velocardiofacial综合征，并可能在其他遗传疾病影响心血管发育。

DESCRIPTION (provided by applicant): Tbx1 is required for cardiovascular development in human, mouse and zebra fish. Since the initial recognition of the role of this gene in development, there has been considerable progress in the analysis of mutants that led to novel hypotheses. Tbx1 is a T-box transcription factor required for segmentation of the embryonic pharynx, patterning of the aortic arch, and morphogenesis of the outflow tract of the heart. However, further knowledge acquisition about this gene would be limited if we do not address two fundamental questions: what are the critical players in the regulation of the Tbx1 gene, and what are the targets of the Tbx1 protein. The Tbx1 gene has an exquisitely dynamic regulation, and here we show that this is associated with time-specific roles during embryogenesis. For example, early expression is required for cardiovascular development while late expression is required for thymic organogenesis and palatogenesis. In addition, we show tissue specific requirements for Tbx1 function during cardiovascular development. This proposal builds upon these new data to search for regulators and targets of Tbx1 that are important at the critical times and tissues. The overall aim is to establish hard links in the genetic pathway within which Tbx1 functions. We believe that this work will lead to genes causing or modifying congenital heart disease. In the first specific aim we will use novel approaches to identify genetic elements necessary for Tbx1 regulation in the pharyngeal endoderm, a key tissue for Tbx1 function, and will also determine if Tbx1 expression in this tissue is sufficient to rescue the cardiovascular abnormalities seen in mutants. In the second specific aim, we will use a combination of transcriptome analysis and chromatin immunoprecipitation assay to identify transcriptional targets. Preliminary data show the power of this approach. In addition, we propose in vitro and in vivo validation of candidate target genes. This project addresses directly the function of Tbx1 in cardiovascular development as defined by upstream regulation of the gene and transcriptional targets of the protein in relevant tissues. Data should provide the dissection of a genetic network disrupted in DiGeorge and Velocardiofacial syndromes, and possibly in other genetic disorders affecting cardiovascular development.