FACTORS INVOLVED IN TRANSCRIPTION BY RNA POLYMERASE II

拟议研究的总体目标是了解对 RNA聚合酶II转录的延伸期。这个对照 这一过程是由导致RNA聚合酶II的负面因素介导的 在启动子和启动子启动后仅合成简短的转录本 积极的因素，允许从这个早期阻碍伸长的释放。 一个果蝇体外系统将被用来进一步表征三个 最近发现的与控制这一现象有关的因素 从失败的延伸过渡到生产性的延伸。C- RNA聚合酶II大亚基的末端结构域(CTD)已被 将进一步审查其在控制过程中的牵连及其作用。 在伸长过程中，P-TEFb作为CTD激酶的功能将是 已定义。因子2作为潜在的三磷酸腺苷依赖性的参与 终止系数和作为延伸率控制所需的系数 将对流程进行检查。P-TEFA的作用及寻找其他因素 可能涉及的问题将继续进行。尽管最终目标是 生成一个已定义的系统，该系统模拟 Vivo，使用简单定义的延伸率控制系统的可行性 由纯RNA聚合酶II、DC拖尾模板和一组 将研究延伸率控制因素。重要的是要了解 延伸率控制过程，因为它涉及到控制一个大的 包括多个癌基因和病毒转录单位的基因数量 包括HIV-1。对这一控制步骤的研究很可能是 真核基因的表达将有助于更好地理解 癌细胞的异常行为及其控制过程 HIV-1基因组的转录。

The overall goal of the proposed research is to understand the control of the elongation phase of transcription by RNA polymerase II. This control process is mediated by negative factors which cause RNA polymerase II to synthesize only short transcripts after initiation from a promoter and positive factors that allow release from this early block in elongation. A Drosophila in vitro system will be used to further characterize three factors that were recently identified as being involved in controlling this transition from abortive elongation into productive elongation. The C- terminal domain (CTD) of the large subunit of RNA polymerase II has been implicated in the control process and its role will be further examined. The function of P-TEFb as a CTD kinase operating during elongation will be defined. The involvement of factor 2 as a potential ATP dependent termination factor and as a factor required for the elongation control process will be examined. The role of P-TEFa and search for other factors that may be involved will be continued. Although the ultimate goal is to generate a defined system that mimics initiation and elongation control in vivo, the feasibility of using a simple defined elongation control system consisting of pure RNA polymerase II, a dC-tailed template, and a set of elongation control factors will be examined. It is vital to understand the elongation control process because it is involved in controlling a large number of genes including many oncogenes and viral transcription units including HIV-1. It is likely that the study of this controlling step in eucaryotic gene expression will lead to a better understanding of the aberrant behavior of cancer cells and the process that controls the transcription of the HIV-1 genome.