GENETIC ANALYSIS OF ZEBRAFISH EMBRYO DEVELOPMENT

斑马鱼是研究胚胎发生的首选脊椎动物模型，因为其快速的透明胚胎离体发育。 遗传学和胚胎学研究表明，胚胎发生的调控在斑马鱼和哺乳动物之间是高度保守的。 具体来说，几乎所有重要的造血调节因子在斑马鱼中都有类似的功能。 我的实验室一直在用斑马鱼研究造血的遗传控制。我们对RUNX 1和CBFB的作用特别感兴趣，这两个基因在人类白血病中经常受到影响。 以前，我们开发了一种在runx 1基因中具有截短突变（W84 X）的斑马鱼品系。这条线的表征表明，胎儿（或斑马鱼的幼虫）和成人造血共享一个共同的干细胞池，但runx 1只需要启动幼虫造血。 现在，我们已经通过一种新的技术开发了几个cbfb突变株，称为锌指核酸酶。对这些细胞系的初步分析表明，cbfb是造血正常发育所必需的。我们将继续分析这些cbfb突变株系，以便更好地了解cbfb在造血和其他发育过程中的功能。 我们还产生了携带转基因CBFB-MYH 11的斑马鱼品系，该转基因在许多人类白血病病例中发现。CBFB-MYH 11转基因在其表达的诱导控制机制下，因此我们可以在发育过程中的任何时间点表达转基因。我们希望利用这些细胞系来描述这个重要的白血病基因的功能。 实验室的另一项主要工作是使用斑马鱼作为体内模型来验证和确认小分子的生物学效应，这些小分子是通过我们开发新型抗白血病药物的其他项目产生的。斑马鱼还可用于这些化学品的毒性研究。迄今为止，我们的经验表明，斑马鱼是一个敏感和非常快速的体内系统，用于这些目的。

The zebrafish is the vertebrate animal model of choice for studies of embryogenesis due to its rapid ex vivo development of transparent embryos. Genetic and embryological studies indicate that the regulation of embryogenesis is highly conserved between zebrafish and mammals. Specifically, virtually all the important regulators of hematopoiesis have homologs in the zebrafish that perform similar functions. My lab has been using zebrafish to study the genetic control of hematopoiesis. We are especially interested in the roles of RUNX1 and CBFB, two genes frequently affected in human leukemias. Previously we developed a zebrafish line with a truncation mutation (W84X) in the runx1 gene. Characterization of this line showed that fetal (or larval in zebrafish) and adult hematopoiesis share a common stem cell pool, but runx1 is only required for the initiation of larval hematopoiesis. Now we have developed several cbfb mutant lines through a novel technology called zinc finger nuclease. Preliminary characterization of these lines revealed that cbfb is required for the proper development of definitive hematopoiesis. We will continue our analysis of these cbfb mutant lines for a better understanding of cbfb function in hematopoiesis, as well as other developmental processes. We have also generated zebrafish lines carrying transgene CBFB-MYH11, which is found in many human leukemia cases. The CBFB-MYH11 transgene is under an inducible control mechanism for its expression, so we can express the transgene at any time point during development. We hope to use these lines to characterize the function of this important leukemia gene. Another major effort in the lab is to use the zebrafish as an in vivo model to validate and confirm the biological effects of small molecules, which are being generated through our other project for the development of novel anti-leukemia drugs. The zebrafish also serve the function of toxicity studies for these chemicals. Our experience so far has demonstrated that the zebrafish is a sensitive and extremely fast in vivo system for these purposes.