9734170 Rolfes Regulation of gene expression at the transcriptional level is important to cells in order to link extracellular conditions with metabolism. The ADE genes of the yeast Saccharomyces cerevisiae provide an excellent model system to learn about the fundamental mechanisms that eukaryotic cells use to regulate gene expression in response to extracellular conditions. The regulation of the ADE5, 7 gene uses regulatory schemes that are conserved in higher eukaryotic cells, namely, multiple regulatory circuits to control gene expression, a common DNA element that binds multiple transcription factors, and combinatorial control arising from the specific interactions of different transcription factors at specific promoter elements. The objectives of this research are to characterize the molecular interactions between the positive transcriptional activators BAS1 and BAS2 with DNA, determine domains for transcriptional activation and protein-protein interaction, and characterize chromosomal mutants and dosage-dependent suppressors to identify additional regulatory components in a signal transduction pathway linking extracellular conditions to the transcriptional activators. The results of these experiments will lead to a deeper understanding of the precise mechanisms used to regulate this locus. The insights gained from this study will shed light on the regulation of gene expression in other eukaryotic cells. Science education is an integral part of modern life. The fruits of science are visible in the advances made in medicine, agriculture and technology. Since the impact of science in society is great, a deeper understanding of what science is and how it works is important for students of today. The ultimate in education in the sciences is achieved via substantial research experience. At the undergraduate level, this type of involvement in science is difficult to achieve because it requires a major investment of time for both the student and faculty member. The objectives of the education plan are to develop a significant nexus of research and undergraduate education in the laboratory, enhance the research orientation of a course in genetics, direct the development of a concentration in molecular biology within the biology major, and participate in special programs aimed at increasing student access to, and awareness, of research opportunities. Purine nucleotides are essential components of cells, composing DNA and RNA, participating in energy transfer and serving as signaling molecules. Cells maintain pools of purine nucleotides to participate in these different reactions. Maintenance of nucleotide pools is essential for ce!ls, and several human disorders arise from the disruption of these pools, including the syndromes severe combined immunodeficiency (SCIDS) and Lesch-Nyhan. The results of this study will provide an understanding of how S. cerevisiae regulates the synthesis of purine nucleotides. Understanding how these regulatory mechanisms work in yeast provides a model for purine regulation in human cells.
