CONTROL OF GENE EXPRESSION DURING DROSOPHILA DEVELOPMENT

需要遗传信息的差异表达来指导 将未分化的受精卵发育成复合体， 多细胞生物体。我们用黑腹果蝇作为理想的 用于研究发育控制机制的模型系统 调控的基因表达。片段基因Fushi Tarazu(FTZ)是 在早期胚胎发育中以复杂的模式表达。在 细胞胚层，FTZ RNA分布在七个均匀分布的区域 胚胎周围的条纹。我们已经确定了两种增强剂 FTZ基因以FTZ样条带模式指导基因表达 当连接到异源启动子时。 本研究的重点是FTZ的“近端增强子”，它是 包含正确信息最多的法规要素 自贸区条纹的空间表达。作为这项研究的一部分，我们有 鉴定了近端最小的顺式作用调控序列 增强剂。已经采取了一种生化方法来鉴定反式- 与增强子相互作用的作用因子，以指导空间 和FTZ表达的时间受限模式 胚胎发生。这种不偏不倚的生化方法使我们能够 并提纯正负调控的转录因子 FTZ表达的动态演变模式。特定突变 引入每个已识别的结合基序将使我们能够 探索已鉴定结合部位的体内相关性。一种蛋白质 与重要调控区域的相互作用将被净化到 同质性。氨基酸序列数据将用于生成探针 用于基因克隆。在未来，新的结构和功能 已鉴定的自贸区调节蛋白(S)将在体外和在 活着。 这项工作的长期目标取决于这样一个前提，即 控制胚胎发育的策略是保守的 在整个动物界，例如， 白粉菌发育调控基因中同源盒的保守性 种类繁多。因此，本研究将提供一个框架 为了理解决定和决定的分子机制 在果蝇和高等生物中的分化。

Differential expression of genetic information is required to direct the development of an undifferentiated, fertilized egg into a complex, multicellular organism. We are using Drosophila melanogaster as a ideal model system to study the mechanisms controlling developmentally regulated gene expression. The segmentation gene fushi tarazu (ftz) is expressed in a complex pattern during early embryogenesis. In the cellular blastoderm, ftz RNA is distributed in seven evenly spaced stripes that surround the embryo. We have identified two enhancers of the ftz gene that direct gene expression in ftz-like striped patterns when linked to a heterologous promoter. This study is focused on the ftz "proximal enhancer" which is the regulatory element that contains the most information for the correct spatial expression of ftz stripes. As part of this study, we have identified minimal cis-acting regulatory sequences within the proximal enhancer. A biochemical approach has been taken to identify the trans- acting factors that interact with the enhancer to direct the spatially and temporally restricted pattern of ftz expression during embryogenesis. This unbiased biochemical approach allows us to identify and purify transcription factors that positively and negatively regulate the dynamically evolving pattern of ftz expression. Specific mutations introduced into each of the identified binding motif will allow us to probe the in vivo relevance of identified binding sites. A protein interacting with an important regulatory region will be purified to homogeneity. Amino acid sequence data will be used to generate probes for gene cloning. In the future, the structure and function of the newly identified ftz regulatory protein(s) will be analyzed in vitro and in vivo. The long term goals of this work rest upon the premise that basic strategies controlling embryonic development have been conserved throughout the animal kingdom, as evidenced, for example, by the conservation of the homebox in developmentally regulated genes of a variety of species. The present studies will thus provide a framework for understanding the molecular mechanisms underlying determination and differentiation in Drosophila as well as in higher organisms.