STRUCTURE AND FUNCTION OF NUCLEIC ACIDS

这个项目涉及基因表达的控制和两个 目前正在调查这一问题的各个方面。控制fo基因 表达可以在转录启动的水平上进行。我们 研究了两种细菌转录调控的机制 操纵子，紫胶操纵子和博伊丁操纵子。目前我们正在研究 转录起始过程中程序化模式的控制 噬菌体T4的感染循环。我们还对 肌动蛋白基因在酿酒酵母中的表达和功能调控。 大多数RNA分子在一系列的转录后改变 这些反应统称为RNA加工。现在很清楚的是，RNA 加工在真核基因的表达中起着重要作用。这个 最近对真核基因结构的阐明揭示了一种新的 组织原则。真核基因经常被 非编码序列称为插入序列或内含子。这些 在一种新的加工反应中从RNA前体中去除序列 这被称为RNA剪接。 我们是第一个在体外证明了RNA剪接反应的人 这种酶与酵母tRNA前体有关。我们正在继续研究 TRNA剪接反应，并提出研究mRNA的程序 拼接。 最近开发出了强大的新技术，使体外培养 基因的改变和它们返回到有机体(转化)。这个 最有效的诱变策略需要有机合成 寡聚核苷酸的技术源于 霍拉纳。我们建议使用这些技术来合成寡核苷酸 产生精确的基因变化以研究其发病机制 核糖核酸合成的控制。

This project is concerned with the control of gene expression and two aspects of this problem are currently being investigataed. Control fo gene expression may be exerted at the levels of initiation of transcription. We have studied the mechanisms of transcriptional control in two bacterial operons, the lac operon and the boitin operon. Currently we are studying the control of the programmed pattern of transcriptional initiation during the infectious cycle of bacteriophage T4. We are also concerned with the control of expression and the function of the actin gene in S. cerevisiae. Most RNA molecules are post-transcriptionally altered in a series of reactions collectively known as RNA processing. It is now clear that RNA processing plays a major role in the expression of eukaryotic genes. The recent elucidation of eukaryotic gene structures has revealed a new principle of organization. Eukaryotic genes are frequently interrupted by non-coding sequences known as intervening sequences or introns. These sequences are removed from RNA precursors in a new processing reaction called RNA splicing. We were the first to demonstrate the RNA splicing reaction in vitro - in this ase with yeast tRNA precursors. We are continuing the study of the tRNA splicing reaction and propose procedures for the investigation of mRNA splicing. Powerful new techniques have recently been developed allowing the in vitro alteration of genes and their return to the organism (transformation). The most powerful of the mutagenic strategies requires the organic synthesis of oligonucleotides by techniques which derive from the pioneering efforts of Khorana. We propose to use these techniques to synthesize oligonucleotides to produce precise alterations of genes in order to study the mechanism of control of RNA synthesis.