Archaeal Transcription Termination

描述(由申请人提供)： 古细菌转录与真核细胞的POL II转录有密切的同源性，但涉及的分子成分要少得多。因此，古生菌转录系统为探索POL II转录机制和研究通常与遗传疾病和癌症相关的异常转录提供了简单得多的模型方法。Eurya chaea也含有古生物组蛋白，将其DNA包装成古核小体，具有与真核核小体中心的(H3/H4)2组蛋白四聚体相同的基本结构、DMA包裹和致密特性。因此，古生菌转录系统也可以直接处理组蛋白和染色质施加的调控。到目前为止，只有古生物的转录起始被详细研究过。关于古生菌转录延伸的研究很少，在体外也没有建立古生菌转录终止的机制。拟议的实验将建立一个古生菌体外转录系统，显示转录终止，并将识别在古生代中直接终止转录的分子信号/蛋白质。我还将确定古生菌RNA聚合酶如何通过古生菌核小体模板转录，并决定核小体的命运。

DESCRIPTION (provided by applicant): Archaeal transcription shares close homology with eukaryotic Pol II transcription but involves many fewer molecular components. Archaeal transcription systems therefore offer much simpler model approaches to probing the mechanics of Pol II transcription and investigating the aberrant transcription often associated with genetic diseases and cancers. Euryarchaea also contain archaeal histones that package their DMA into archaeal nucleosomes which have the same basic structure, DMA wrapping and compaction properties as the (H3/H4)2 histone tetramer at the center of the eukaryotic nucleosome. Archaeal transcription systems can therefore also directly address regulation imposed by histones and chromatin. To date, only archaeal transcription initiation has been studied in detail. Very little is known about archaeal transcription elongation, and archaeal transcription termination has not been established in vitro. The experiments proposed will establish an archaeal in vitro transcription system that exhibits transcription termination, and will identify the molecular signals/proteins that direct termination in Archaea. I will also determine how an archaeal RNA polymerase transcribes through an archaeal nucleosome template and determine the fate of the nucleosome.