CIS-ACTING ELEMENTS THAT REGULATE EXPRESSION OF THE BETA-GLOBIN GENE FAMILY

更全面地了解控制正常的机制 人β珠蛋白组织和发育阶段特异性表达 基因家族对于开发新的治疗策略至关重要。 我们现在已经建立了一个人β珠蛋白基因的转基因模型 在个体发育期间通过完整的人β珠蛋白的转移进行调节 酵母人工染色体（YACs）我们的长期目标是利用 β珠蛋白YAC转基因模型，以更精确地定义 顺式作用调节序列，其指导组织和阶段特异性 人β珠蛋白基因家族的表达。我们的假设是 多个序列元件参与了β基因的发育过程 基因表达位于个体内部或紧邻个体侧翼， 基因及其启动子。为了验证这一假设，我们将使突变 在假定的调控区中使用同源定向重组，和 分析它们对人类γ和β珠蛋白基因的调节作用 表情我们还将制定一项补充战略， 胚胎干细胞（ES）中人β珠蛋白基因座的突变 来自我们的转基因品系的品系，所述转基因品系携带单个拷贝的 人β珠蛋白基因座。基于ES细胞的方法将使我们能够 直接比较转基因植物中每种突变的影响， 具有相同染色体整合位置的人β珠蛋白基因座。 携带人β珠蛋白基因座的转基因小鼠和ES细胞系 对于评估已知反式作用因子的作用也是有价值的。 并将提供独特的模式，以界定新的功能， 确定了调节人类β珠蛋白基因家族的遗传位点。 我们的分析将提供一个更完整的了解序列 在发育过程中珠蛋白基因调控所需的元件， 最终帮助开发新的遗传和药理学 SCD的治疗方法。

A more comprehensive understanding of the mechanisms that control normal tissue-and developmental stage-specific expression of human beta globin gene family is essential for the development of new treatment strategies. We have now generated a transgenic model of human beta globin gene regulation during ontogeny by transfer of the intact human beta globin locus in Yeast Artificial Chromosomes (YACs). Our long-term goal is to use the beta globin YAC transgenic model to more precisely define the role of cis-acting regulatory sequences that direct tissue- and stage-specific expression of the human beta globin gene family. Our hypothesis is that multiple sequence elements involved in the developmental program of beta gene expression reside within, or immediately flanking the individual genes and their promoters. To test this hypothesis, we will make mutations in putative regulatory regions using homology-directed recombination, and analyze their effect on the regulation of human gamma and beta globin gene expression. We will also develop a complementary strategy by making mutations in the human beta globin locus in embryonic stem (ES) cells lines derived from our transgenic lines carrying a single copy of the human beta globin locus. The ES cell-based approach will allow us to directly compare the effects of each of the mutations in a transgenic human beta globin locus with the same chromosomal position of integration. Transgenic mice and ES cell lines carrying the human beta globin locus will also be valuable for assessing the role of known trans-acting factors and will provide unique models for defining the function of newly identified genetic loci in regulating the human beta globin gene family. Our analysis will provide a more complete understanding of the sequence elements required for globin gene regulation during development, and may ultimately assist in the development of novel genetic and pharmacological approaches to the treatment of SCD.