TRANSCRIPTION ELONGATION FACTORS IN YEAST

基因表达的适当调节是必要的，以正常 生长和发育的发生。转录过程代表了 第一步是选择细胞将使用的遗传信息。 然而，选择合适的基因来解码只是一个问题。 开始.一旦RNA聚合酶及其相关因子识别出 正确的基因，转录过程必须确保准确， 有效的延伸，直到完整的转录单位已被 解码也就是说，虽然准确选择哪些基因的细胞 需要转录开始转录调节，高效 延伸决定了遗传信息是否被转化 转化为对细胞有用的产物。有大量的基因在 人和其它真核细胞及其病毒， 在伸长水平上受到特异性调节。比如这些 包括几种原癌基因（c-myc、c-myb、c-fos）、腺苷 脱氨酶，应激反应基因的集合，以及HIV-1和HIV-2。 清楚地了解控制转录的机制 通过这些和其他基因的延伸是理解 正常发育以及癌症和艾滋病等疾病。 为了增加我们对转录控制的了解 延伸过程中，遗传和生物化学的方法将是最 强大.这种结合在萌芽期最容易进行 酵母，酿酒酵母。有广泛的保护在 蛋白质组分和转录的生化过程， 真核生物因此，通过对这种酵母的研究所学到的很多东西将 可以直接应用于哺乳动物细胞中的类似反应。这 建议将解决几个问题的因素，调节 RNA聚合酶II的延伸反应。而转录延长 因子TFIIS将进行详细分析，实验设计将 也确保识别和表征新的因素， 除了TFIIS参与伸长率控制。具体 目的包括：（1）识别和表征功能替代品， 转录延长TFIIS;（2）鉴定与转录延长TFIIS相互作用的蛋白质。 TFIIS并确定其功能相关性;（3）鉴定氨基酸 在S.（4）鉴定 阻断S.体内酿酒酵母RNA聚合酶II 和体外培养。

The proper regulation of gene expression is necessary in order for normal growth and development to occur. The transcription process represents the first step in selecting which genetic information the cell will use. However, the selection of the proper genes to decode is only the beginning. Once RNA polymerase and its associated factors identify the correct genes, the transcription process must insure accurate and efficient elongation until the complete transcription unit has been decoded. That is, while the accurate selection of which genes the cell needs to transcribe begins transcriptional regulation, efficient elongation determines whether or not the genetic information is converted into a product useful to the cell. There are a large number of genes in human, and other eukaryotic, cells and their viruses which are specifically regulated at the level of elongation. For example, these include several protooncogenes, (c-myc, c-myb, c-fos), adenosine deaminase, a collection of stress response genes, and HIV-1 and HIV-2. Clearly understanding the mechanisms which control transcription elongation through these and other genes is fundamental to understanding normal development as well as such diseases as cancer and AIDS. In order to increase our knowledge of the controls over the transcript elongation process, a genetic and biochemical approach would be most powerful. This combination is most easily carried out in the budding yeast, Saccharomyces cerevisiae. There is extensive conservation in the protein components and biochemical processes of transcription among eukaryotes. Thus, much of what is learned by studies of this yeast will be immediately applicable to similar reactions in mammalian cells. This proposal will address several questions about factors which regulate the elongation reaction of RNA polymerase II. While transcript elongation factor TFIIS will be analyzed in detail, the experimental design will also insure the identification and characterization of new factors in addition to TFIIS that participate in elongation control. The Specific Aims include: (1) Identify and characterize functional substitute(s) for transcript elongation TFIIS; (2) Identify proteins which interact with TFIIS and determine their functional relevance; (3) Identify amino acid residues important for TFIIS function in S. cerevisiae; (4) Identify sites which block elongation by S. cerevisiae RNA polymerase II in vivo and in vitro.