CAREER: A Polymerase Switch in the Synthesis of rRNA in Yeast

随着我们对细胞结构和功能的分子基础有了更深入的了解，遗传学、分子生物学和细胞生物学之间的区别逐渐消失。本科生通常在这些学科中选修不同的课程，他们经常将信息划分为特定的课程，而没有认识到这些细胞过程的相互依赖性。这种分裂阻碍了对基本生物学原理的认识。该项目包括三个教育目标：三个学期的课程，整合遗传学，分子和细胞生物学，强调细胞相互作用；相应的两学期实验课程，通过基础实验强化基本原理；让学生通过独立研究来探索发现的过程。独立研究将集中在rRNA合成中的聚合酶开关的研究上。在呼吸缺陷的酿酒酵母菌中，rRNA是由RNA聚合酶I和RNA聚合酶II合成的。在这些细胞中，一个与pol I启动子重叠的隐性pol II rDNA启动子被用来合成一个等效的35S前体rRNA，该前体rRNA可以减轻对pol I的需求。这一新发现在rRNA合成的调控中引入了新的问题，特别适合说明科学探究在改变细胞功能认知中的作用。本研究的目的是：1。定义rDNA pol II转录的序列信号。2. 确定rDNA pol II转录所需的调控因子。3. 研究pol II rRNA的功能。剖析rRNA的poll II转录的作用，为学生介绍科学发现在扩大我们对多细胞过程的理解中的作用提出了一个有趣的问题。rRNA合成从pol I到pol II的转换涉及多个细胞过程的相互作用，包括：胞间通讯，转录激活和沉默，以及rDNA片段拷贝的优先切除和复制。学生将通过合成各种细胞过程来研究这些相互作用，这些细胞过程交织在一起产生pol II合成rRNA。随着我们对细胞结构和功能的分子基础有了更深入的了解，遗传学、分子生物学和细胞生物学之间的区别逐渐消失。这个项目将包括开发一个三个学期的课程，整合通常在遗传学，细胞和分子生物学的单独课程中获得的信息。重点将放在信息的综合而不是划分，以及细胞过程的相互作用作为解决问题的框架。此外，通过参与实验室练习和追求独立研究，学生将亲眼目睹科学探究的过程。在呼吸缺陷的酵母菌株是由RNA聚合酶I和RNA聚合酶II合成的。剖析rRNA的pol II转录的作用提出了一个有趣的问题，将用于向学生介绍科学发现在扩大我们对多细胞过程的理解中的作用。学生将通过合成各种细胞过程来研究这些相互作用，这些细胞过程交织在一起产生pol II合成rRNA。＊＊＊

9722253 Conrad-Webb As we achieve greater understanding of the molecular basis of cellular structure and function, the distinctions among genetics, molecular biology and cellular biology fade. Undergraduate students, who usually take separate courses in these disciplines, often compartmentalize information to the specific course and do not recognize the interdependence of these cellular processes. Such fragmentation impedes the recognition of basic biological principles. This project includes three educational objectives: a three semester course which integrates genetics, molecular and cellular biology and emphasizes cellular interactions; a corresponding two semester laboratory course to reinforce fundamental principles by conducting basic experiments; and exposure of students to the process of discovery through independent research. The independent research will focus on the study of a polymerase switch in the synthesis of rRNA. In respiratory deficient strains of Saccharomyces cerevisiae, rRNA is synthesized by both RNA polymerase I and RNA polymerase II. In these cells, a cryptic pol II rDNA promoter that overlaps the pol I promoter is used to synthesize an equivalent 35S precursor rRNA that can alleviate the requirement for pol I. This novel finding introduces new questions in the regulation of rRNA synthesis and is particularly well suited to illustrating the role of scientific inquiry in changing perceptions of cellular function. The objectives of this research are to: 1. Define the sequence signals for pol II transcription of rDNA. 2. Identify regulatory factors required for pol II transcription of rDNA. 3. Investigate the function of pol II rRNA. Dissecting the role of poll II transcription of rRNA presents an intriguing problem for the introduction of students to the role of scientific discovery in expanding our understanding multiple cellular processes. The switch in rRNA synthesis from pol I to pol II involves the interactions of multiple cellular processes including : interorganellar communication, transcriptional activation and silencing, and preferential excision and replication of rDNA episomal copies. Students will be investigating these interactions by synthesizing the various cellular processes that intertwine to produce pol II synthesis of rRNA. %%% As we achieve greater understanding of the molecular basis of cellular structure and function, the distinctions among genetics, molecular biology and cellular biology fade. This project will include the development of a three semester course to integrate the information usually acquired in separate courses in genetics, cell and molecular biology. Emphasis will be placed on the synthesis rather than compartmentalization of information, and the interactions of cellular processes as a framework for problem solving. Furthermore, by participation in laboratory exercises and in the pursuit of independent research, students will witness first hand the process of scientific inquiry. In respiratory deficient strains of yeast is synthesized by both RNA polymerase I and RNA polymerase II. Dissecting the role of pol II transcription of rRNA presents an intriguing problem which will be used to introduce students to the role of scientific discovery in expanding our understanding multiple cellular processes. Students will be investigating these interactions by synthesizing the various cellular processes that intertwine to produce pol II synthesis of rRNA. ***