GENETICS OF THE TRANSCRIPTION PROCESS

真核RNA聚合酶III负责许多转录因子的转录。 小RNA分子，包括所有的细胞质tRNA。 初级承认 PolIII转录复合物对tRNA基因的特异性存在于 存在于染色质中但可以分离的两种或多种蛋白质 从RNA聚合酶III的全细胞提取物。 形成 防止了tRNA基因和这些蛋白质之间的前起始复合物 通过突变，改变序列内的二氢U和T Psi臂， tRNA编码序列。 这个研究项目的目标是解剖 分离和鉴定各种DNA-蛋白质相互作用， 真核生物tRNA基因转录的起始和终止。 酵母中的赭石抑制tRNA基因提供了独特的机会， 分离并研究tRNA基因中影响转录的两种突变 以及与基因相互作用的蛋白质成分的基因突变 在转录过程中。 可以设想，这种基因的遗传分析可以在以下方面进行： 影响酵母SUP 4 tRNATyr基因表达的突变， 通过对受这些突变影响的蛋白质进行生物化学研究， 为转录过程提供了新的见解。 由于这种方法是 发展，它也应该适用于分子遗传分析， RNA聚合酶II的功能，在酵母中产生mRNA的酶， 其他真核生物

Eukaryotic RNA polymerase III is responsible for the transcription of many small RNA molecules, including all cytoplasmic tRNAs. Primary recognition specificity of tRNA genes by the PolIII transcription complex resides in two or more proteins which are present in chromatin but can be separated from RNA polymerase III in whole cell extracts. Formation of a pre-initiation complex between a tRNA gene and these proteins is prevented by mutations which alter sequences within the Dihydro U and T Psi arms of tRNA coding sequence. The goal of this research project is to dissect apart and identify the various DNA-protein interactions which occur during the initiation and termination of transcription of eukaryotic tRNA genes. Ochre-suppressor tRNA genes in yeast provide unique opportunities to isolate and study both mutations in tRNA genes that affect transcription and mutations in genes for protein components that interact with the genes during transcription. It is envisioned that the genetic analysis of such mutations affecting expression of the yeast SUP4 tRNATyr gene, together with biochemical studies of the proteins affected by these mutations, will provide new insights into the transcription process. As this approach is developed, it should also be applicable to molecular genetic analysis of the function of RNA Polymerase II, the enzyme which makes mRNA in yeast and other eukaryotes.