CARDIAC PROGENITOR CELL DIFFERENTIATION

描述：（改编自研究者摘要）申请人希望 了解心源性转录因子在决定 和心肌细胞的发育。他发现并克隆了一个cDNA 编码心脏调节转录因子，称为Clp-1， 在心源性祖细胞的发育中起重要作用。的 本申请的既定目标是了解Clp-1在以下方面的作用： 通过解决Clp-1在何时、何地以及以何种能力执行其功能， 作为心脏发生的调节器。该提案有四个具体目标。 目的1是针对结构和性质的额外表征。 Clp-1的功能特性，因为它与其潜在的心源性 监管属性。申请人和他的同事将尝试 鉴定负责结合B的Clp-1的结构域 元件MEF-2结合位点，并确定是否 这些相同的结构域介导Clp-1激活心脏MLC-2 体内基因目的2是研究细胞功能， Clp-1，以确定其作为心脏基因的调节因子的作用， 心源性细胞分化这些研究将侧重于确定1） Clp-1作为心源性转录激活因子的潜力 能够参与心脏谱系决定的激活 2）Clp-1不可逆地将前体细胞转化为细胞因子的能力。 心源性细胞谱系，以及3）Clp-1与BMP-2的等级关系， 另一个发育信号是已知的重要承诺， 干细胞到心脏谱系。目标3将侧重于 控制Clp-1表达所需的启动子元件。申请人将 检查小鼠Clp-1基因的启动子区域，以确定 在心源性中胚层细胞中指导表达所需的序列。 目标4将试图确定CLP-1在 体内心源性发育程序的实际阐述。这将 在Clp-1基因座的遗传消除后在敲除小鼠中进行评价。 这些小鼠的发育将主要在以下方面进行： 发育中心脏的形态和组织学状态， 如果出现非心脏表型，异常心脏 发展将在分子水平上进行分析， 正常心脏遗传标记的表达可能在心脏基因组的控制下， Clp-1转录因子。此外，还对转基因植物的生理特性进行了分析。 成年人的心脏将被用来寻找微妙的扰动，导致 心脏功能的变化

DESCRIPTION: (Adapted from the Investigator's Abstract) The applicant hopes to understand the role of cardiogenic transcription factors in the determination and development of cardiac muscle cells. He has identified and cloned a cDNA encoding a cardiac regulatory transcription factor, called Clp-1, that may play an important role in the development of cardiogenic progenitor cells. The stated goal of the current application is to understand the role of Clp-1 in cardiogenesis by addressing when, where and in what capacity Clp-1 performs its function as a regulator of cardiogenesis. The proposal has four specific aims. Aim 1 is directed towards additional characterization of the structural and functional properties of Clp-1 as it relates to its potential cardiogenic regulatory properties. The applicant and his colleagues will attempt to identify the structural domains of Clp-1 that are responsible for binding the B element MEF-2 binding site in the cardiac MLC-2 gene promoter and determine if these same structural domains mediate Clp-1 activation of the cardiac MLC-2 gene in vivo. Aim 2 is directed towards investigating the cellular functions of Clp-1 in order to establish its role as a regulator of cardiac genes and cardiogenic cell differentiation. These studies will focus on determining 1) the potential of Clp-1 to act as a cardiogenic transcriptional activator capable of participating in the activation of cardiac lineage-determining genes, 2) the ability of Clp-1 to irreversibly commit precursor cells to the cardiogenic cell lineage, and 3) the hierarchal relationship of Clp-1 to BMP-2, another developmental signal which is known to be important in commitment of stem cells to the cardiac lineage. Aim 3 will focus on the characterization of promoter elements required for control of Clp-1 expression. The applicant will examine the promoter region of the mouse Clp-1 gene in an effort to define the sequence(s) required for directing expression in cardiogenic mesodermal cells. Aim 4 will attempt to determine the importance and necessity of Clp-1 in the actual elaboration of the cardiogenic developmental program in vivo. This will be evaluated in knockout mice following genetic ablation of the Clp-1 locus. The development of these mice will be followed primarily with respect to the morphological and histological status of the developing heart and secondarily with regard to non-cardiac phenotypes should they arise. Abnormal heart development will be analyzed at the molecular level by assaying for the expression of normal heart genetic markers presumably under the control of the Clp-1 transcription factor. In addition, physiological analysis of transgenic adult hearts will be undertaken to look for subtle perturbations that lead to detectable changes in heart function.