RPG: Molecular Evolution of Gene Transcription in Evolved Strains of Yeast

RPG：酵母进化菌株中基因转录的分子进化

• 批准号: 9408317
• 负责人: Celeste Brown
• 金额: $ 1.8万
• 依托单位: Regents of the University of Idaho
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-07-01 至 1996-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9408317&HistoricalAwards=false
• 关键词: RPG; Molecular; Evolution; Gene; Transcription

9408317 Brown Differences in gene regulation in natural populations of organisms may serve as the most important source of genetic variation for the process of natural selection. The purpose of the proposed research is to investigate one of the molecular aspects of gene regulation, namely gene transcription, in response to positive selection, neutral mutation, and purifying selection. In a glucose-limited environment, genes engaged in glucose metabolism are under strong selection, and the genes for galactose metabolism are not used. Positive selection for enhanced glucose utilization may lead to increased activity of genes involved in galactose metabolism leading to the loss of galactose inducibility in these genes. In this environment, the sole nitrogen source is ammonium sulfate, and yeast must metabolize all amino acids. Genes for amino acid metabolism are critically important for cell growth, and their regulation is subject to purifying selection. The first objective of the proposed work is to assess the effect of positive selection on transcriptional regulation of genes whose products are involved in glucose metabolism; the effect of neutral mutations on the inducibility of genes whose products are involved in galactose metabolism, and the effect of purifying selection on the transcriptional regulation of genes involved in amino acid synthesis. The second objective is to determine whether nucleotide sequence differences in the promoter regions of genes may account for the transcriptional differences.

9408317生物体自然种群中基因调控的布朗差异可能是自然选择过程中最重要的遗传变异来源。这项研究的目的是研究基因调控的分子方面之一，即基因转录，以响应正选择、中性突变和纯化选择。在葡萄糖有限的环境中，参与葡萄糖代谢的基因处于强有力的选择之下，半乳糖代谢的基因没有被使用。提高葡萄糖利用率的正选择可能导致参与半乳糖代谢的基因活性增加，从而导致这些基因中半乳糖的诱导性丧失。在这种环境中，唯一的氮源是硫酸铵，酵母必须代谢所有的氨基酸。氨基酸代谢的基因对细胞生长至关重要，它们的调节受到纯化选择的影响。这项工作的第一个目标是评估正选择对其产物参与葡萄糖代谢的基因转录调控的影响；中性突变对其产物参与半乳糖代谢的基因的诱导性的影响；以及纯化选择对参与氨基酸合成的基因转录调控的影响。第二个目标是确定基因启动子区域的核苷酸序列差异是否可以解释转录差异。