RIBOSOMAL GENES OF YEAST AND THEIR REGULATION

核糖体的合成是一个复杂但受到严格控制的过程。 细胞合成等摩尔量的四个核糖体RNA 细胞核和细胞质中的75种核糖体蛋白，以及 将它们组装成核仁中的核糖体。我们建议在北京学习 酿酒酵母控制转录和转录的机制 核糖体RNA和核糖体蛋白的合成。 核糖体RNA：我们在rDNA重复序列中发现了许多 增强子元素的属性。我们计划找出准确的 这种效果所涉及的序列。我们会问这个增强剂 元素： A)结合特定的转录因子？ B)参与了35S prRNA的转录调控？ C)负责35S prRNA转录的1：1比例和 5S RNA，谁的基因位于增强子和35S起始点之间？ 核糖体蛋白：大多数，如果不是全部的转录速度， 核糖体蛋白基因是紧密耦合的。要了解这一机制 在这种耦合的背后，我们将确定 转录一个核糖体蛋白基因，然后确定是否类似 序列也用于其他核糖体蛋白基因。我们会问，如果 它们的转录和/或调控涉及相同的序列 是否存在针对这些基因的转录因子。最后， 我们将分析核糖体的翻译调控机制 蛋白质合成，重点是检验一个假设 调控分子与m7G帽及其邻近序列相互作用。

The synthesis of ribosomes is a complex but tightly regulated process in which the cell synthesizes equimolar amounts of four ribosomal RNAs in the nucleus, and of seventy-five ribosomal proteins in the cytoplasm, and assembles them into a ribosome in the nucleolus. We propose to study in Saccharomyces cerevisiae the mechanisms controlling both the transcription of ribosomal RNA and the synthesis of ribosomal proteins. Ribosomal RNA: We have identified a sequence in the rDNA repeat with many of the properties of an enhancer element. We plan to identify the precise sequences involved in this effect. We will ask whether this enhancer element: a) binds a specific transcription factor? b) is involved in the regulation of transcription of 35S prerRNA? c) is responsible for the 1:1 ratio of the transcription of 35S prerRNA and 5S RNA, whose gene lies between the enhancer and the 35S initiation site? Ribosomal Protein: The rates of transcription of most, if not all, ribosomal protein genes are tightly coupled. To understand the mechanism behind this coupling we will identify the sequences essential for the transcription of one ribosomal protein gene and then determine if similar sequences are used for other ribosomal protein genes. We will ask if the same sequences are involved in regulation of their transcription and/or whether there is a transcription factor specific for these genes. Finally, we will analyze the mechanism for translational control of ribosomal protein synthesis, with emphasis on testing the hypothesis that a regulatory molecule interacts with the m7G cap and its adjacent sequences.