CONTROL OF RIBOSOMAL GENE TRANSCRIPTION

我们继续对核糖体rna的调控进行长期研究。 酵母中的转录，酿酒酵母。核糖体RNA是 由RNA聚合酶I(Po1I)转录，由超过一半的 细胞的总RNA。顺式作用的DNA元件，以及 控制po1I转录的反式作用蛋白因子有 很大程度上是在过去的工作中发现的。现在的挑战是 了解这些DNA和蛋白质元素是如何发挥作用的 核糖体RNA与细胞的生长速度严格协调。 因为核糖体RNA的生产对人类的经济非常重要 细胞，它受到许多不同层面的监管。因此， 建议通过实验在1)的水平上研究监管 聚合酶本身，2)在 启动子，3)必须在启动前清除的染色质 复杂到难以形成。其他实验将调查所有PO1I 主要代谢转变(甘油/乙醇)过程中的转录机制 葡萄糖)，以确定这些潜在的调节水平中的哪些是 实际使用的。 核糖体RNA是所有活细胞的主要和必不可少的组成部分。 目前尚不清楚po1I转录的改变与 任何疾病状态，但了解核糖体RNA生产是如何协同 与细胞生长相协调是细胞研究中尚未解决的主要问题之一 生物学。

We continue our long-term study of the regulation of ribosomal RNA transcription in the yeast, Saccharomyces cerevisiae. Ribosomal RNA is transcribed by RNA polymerase I (po1I) and comprises over half of the total RNA of the cell. Both the cis-acting DNA elements, as well as the trans-acting protein factors which control po1I transcription have largely been identified in past work. The challenge now is to understand how these DNA and protein elements function to produce ribosomal RNA in strict co-ordination with the growth rate of the cell. Because ribosomal RNA production is so important to the economy of the cell, it is subject to regulation at many different levels. Thus, experiments are proposed to study regulation at the level of 1) the polymerase itself, 2) the pre-initiation complex that forms at the promoter, 3) chromatin which must be cleared for the pre-initiation complex to form. Other experiments will survey all of the po1I transcription machinery during a major metabolic shift (glycerol/ethanol to glucose) to determine which of these potential regulatory levels are actually utilized. Ribosomal RNA is a major and essential component of all living cells. Alterations in po1I transcription are not known to be associated with any disease state, but understanding how ribosomal RNA production is co- ordinated with cell growth is one of the major unsolved problems of cell biology.