Regulation of mesodermal progenitors in transgenic zebrafish

描述(由申请人提供)： 脊椎动物的大量证据表明，前躯干和身体其余部分的发育是不同的调节。以往利用突变体、基因敲除、吗啡和mRNA注射的研究已经提供了非常重要的信息，即信号和转录因子在建立原肠胚早期胚胎脊椎动物的身体计划中所起的作用。然而，由于早期原肠胚胚胎模式的改变会导致如此严重的胚胎缺陷，因此很难研究身体大部分发育的后期阶段。利用含有热休克诱导的细胞自主信号和转录调控因子的转基因株，再加上我们开发的一种新的转基因株，使我们能够暂时和特异性地标记中胚层前体细胞，我们现在有能力确定中胚层前体细胞是如何受信号和T-box转录因子调控的，在体细胞发生过程中逐步分化，这一过程对于形成正常的身体是必不可少的，并且在所有脊椎动物中都是保守的。这里描述的研究利用斑马鱼在活胚胎中单细胞水平分析中胚祖细胞的能力，使用细胞移植在正常背景下实验性地研究细胞自主扰动的细胞。这一新的方法将使我们能够检查当所有胚胎细胞在信号或转录方面发生变化时被掩盖的细胞行为。研究表明，特别是在哺乳动物中，中胚层祖细胞是一个类似干细胞的群体，通常有一定的寿命。随着转基因技术的最新进展，再加上使用荧光记者研究活胚胎中的祖细胞的能力，斑马鱼为了解脊椎动物干细胞在体内是如何调控的提供了一个很好的模型系统。由于干细胞在治疗许多疾病方面有很大的希望，这里描述的研究将提供关于控制干细胞维持和组织形成的信号网络和转录因子的有价值的信息。研究表明，特别是在哺乳动物中，中胚层祖细胞是一个类似干细胞的群体，通常有一定的寿命。随着转基因技术的最新进展，再加上使用荧光记者研究活胚胎中的祖细胞的能力，斑马鱼为了解脊椎动物干细胞在体内是如何调控的提供了一个很好的模型系统。由于干细胞在治疗许多疾病方面有很大的希望，这里描述的研究将提供关于控制干细胞维持和组织形成的信号网络和转录因子的有价值的信息。

DESCRIPTION (provided by applicant): A large body of evidence in vertebrates shows that the development of the anterior trunk and the rest of the body are differentially regulated. Previous studies using mutants, knockouts, morpholinos and mRNA injection have provided very important information on the role of signaling and transcription factors in establishing the embryonic vertebrate body plan during the early gastrula stages. However, because alterations in the patterning of the early gastrula embryo cause such severe embryological defects, it has been difficult to study later stages when most of the body develops. Using transgenic lines containing heat-shock inducible cell autonomous regulators of signaling and transcription, together with a new transgenic line we developed that allows us to temporally and specifically label the mesodermal progenitors, we now have the ability to determine how the mesodermal progenitors are regulated by signaling and T-box transcription factors to progressively differentiate during somitogenesis, a process that is essential for forming a normal body and is conserved in all vertebrates. The studies described here take advantage of the ability in zebrafish to analyze the mesodermal progenitors at the single-cell level in living embryos, using cell transplants to study experimentally cell-autonomously perturbed cells within a normal background. This novel approach will allow us to examine cell behaviors that are obscured when all of the embryonic cells have alterations in signaling or transcription. Studies, particularly in mammals, show that the mesodermal progenitors are a stem-cell like population, which normally has a defined lifetime. With recent advances in the technology to produce transgenic lines, combined with the ability to study progenitors in living embryos using fluorescent reporters, zebrafish provides an excellent model system for understanding how vertebrate stem cells are regulated in vivo. As stem cells have great promise for the treatment of many diseases, the studies described here will provide valuable information about the signaling networks and transcription factors that control stem cell maintenance and tissue formation. Studies, particularly in mammals, show that the mesodermal progenitors are a stem-cell like population, which normally has a defined lifetime. With recent advances in the technology to produce transgenic lines, combined with the ability to study progenitors in living embryos using fluorescent reporters, zebrafish provides an excellent model system for understanding how vertebrate stem cells are regulated in vivo. As stem cells have great promise for the treatment of many diseases, the studies described here will provide valuable information about the signaling networks and transcription factors that control stem cell maintenance and tissue formation.