GENETIC ANALYSIS OF RNA POLYMERASE II TRANSCRIPTIONAL REGULATION IN DROSOPHILA

我们有兴趣了解 蛋白质编码基因的转录在体内受到调节。电流 转录调控的模型主要基于体外 在非生理条件下进行的研究， 纯化的一般转录因子，合成的激活蛋白， 和非染色质DNA模板。通过研究 这些基因是果蝇正常发育所必需的 我们希望能够识别顺式和 在体内发挥调节作用并决定 不同因素的协调作用如何建立 真核细胞的广泛转录库。为此我们 正在研究果蝇sevenless（sev）基因的转录。 选择sev基因是因为水平的微小改变或 SEV转录模式导致在细胞中容易观察到的表型， 发育中的苍蝇，使SEV转录适合遗传 解剖从SEV研究中获得的知识将在 一个基因组范围的基础，以评估的一般性， 在我们的实验室进行的基于SEV的遗传筛查 确定了RNA聚合酶（pol）II组分中的突变 前起始复合物[TBP相关因子（TAF）60和TAF 110 和RNA聚合酶II亚基]以及调节 转录通过其对染色质结构的影响[三胸 组（TRX-G）基因、RPD 3和SIN 3]。另外的突变 也可能编码转录调节因子。 突变果蝇的表型和分子特征正在 用于鉴定受转录调控的基因， 编码的因素，并分析基因之间的相互作用 突变果蝇被用来评估 编码的因素。

We are interested in understanding how transcription of protein-coding genes is regulated in vivo. Current models for transcriptional regulation are based largely on in vitro studies conducted under non-physiological conditions using highly purified general transcription factors, synthetic activator proteins, and non-chromatin DNA templates. By studying transcription of endogenous genes that are required for proper Drosophila melanogaster development, we hope to identify cis- and trans-acting factors that play regulatory roles in vivo and determine how the coordinated action of different sets of factors establish the broad transcriptional repertoire of eukaryotic cells. To this end, we are studying transcription of the Drosophila sevenless (sev) gene. The sev gene was chosen because minor alterations in the level or pattern of sev transcription cause easily observable phenotypes in the developing fly, making sev transcription amenable to genetic dissection. Knowledge gained from studies of sev will be tested on a genome wide basis to assess the generality of the Sev model.Sev-based genetic screens conducted in our laboratory have identified mutations in components of the RNA polymerase (pol) II preinitiation complex [TBP-associated factor (TAF)60 and TAF110 and RNA pol II subunits] as well as factors that modulate transcription through their affects on chromatin structure [Trithorax group (TRX-G) genes, RPD3, and SIN3]. Additional mutations have been identified that may also encode transcriptional regulators. Phenotypic and molecular characterization of mutant flies is being used to identify genes that are transcriptionally regulated by the encoded factors, and analysis of genetic interactions between mutant flies is being used to assess functional interactions between the encoded factors.