Genetic regulation of genome stability in yeast

酵母基因组稳定性的遗传调控

• 批准号: 7448623
• 负责人: THOMAS PETES
• 金额: $ 37.87万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7448623
• 关键词: ATM gene; ATR gene; Affect; Aphidicolin; Base Pairing; Cell Cycle; Chromatin Modeling; Chromosomal Breaks; Chromosome Fragile Sites; Chromosome Structures; Chromosome abnormality; Chromosomes; DNA; DNA Microarray Chip; DNA Microarray format; DNA Polymerase Inhibitor; DNA Sequence; DNA Sequence Rearrangement; DNA damage checkpoint; Diploidy; Event; Evolution; Fungal Genome; Gel; Gene Dosage; Genes; Genetic; Genetic Recombination; Genome; Genome Stability; Genomic Instability; Genomics; Genotype; Goals; Homologous Gene; Investigation; Ionizing radiation; Length; Malignant Neoplasms; Mammalian Cell; Maps; Microarray Analysis; Mutation; Neoplasm Metastasis; Ploidies; Polymerase; Positioning Attribute; Process; Property; Rate; Regulation; Research; Saccharomyces; Saccharomyces cerevisiae; Site; Techniques; Technology; Temperature; Translocation Breakpoint; Yeasts; irradiation; mutant; neoplastic cell; rRNA Genes; telomere

DESCRIPTION (provided by applicant): Genomes can be altered in a variety of ways including single base pair changes, deletions and duplications of sequences, and chromosome rearrangements (translocations and inversions). The rates at which these events occur affect 2 quite different processes. Genetic changes are required for evolution and the rate of these changes, therefore, can in principle affect the rate of evolution. Second, many cancers are associated with elevated rates of chromosome rearrangements, and this type of instability appears to be strongly associated with metastatic tumors. When mammalian cells are treated with aphidicolin (a DNA polymerase inhibitor), the chromosomes are broken at specific sites (fragile sites) that are related to translocation breakpoints observed in tumor cells. High levels of chromosome breaks and other aberrations are also observed in mammalian cells with mutations in the ATM and ATR genes. Our general goal is to mimic this type of genetic instability in the yeast Saccharomyces cerevisae, and to characterize the mechanisms responsible for this instability. Our specific aims are: 1) to determine the DNA sequence properties that characterize yeast fragile sites and to characterize the chromosome rearrangements that are associated with DNA breaks at fragile sites, 2) to characterize chromosome aberrations in yeast strains with mutations in genes affecting DNA damage checkpoints, telomere length regulation, recombination, and/or chromatin assembly; for example, strains with mec1 and/or tel1 genes (yeast homologues of the mammalian ATR and ATM genes, respectively) will be examined, and 3) to understand the genetic instability induced by ionizing radiation. These studies will emphasize techniques that allow examination of the entire yeast genome, including DNA microarray analysis (to detect changes in gene dosage and to map translocation breakpoints), and gel technologies that allow separation of intact chromosomal DNA molecules.

描述（由申请人提供）：基因组可以通过多种方式改变，包括单碱基对改变、序列删除和重复、以及染色体重排（易位和倒位）。这些事件发生的速率影响两个完全不同的过程。遗传变化是进化所必需的，因此，这些变化的速率原则上可以影响进化的速率。其次，许多癌症与染色体重排率升高有关，而这种类型的不稳定性似乎与转移性肿瘤密切相关。当哺乳动物细胞用阿菲迪霉素（一种 DNA 聚合酶抑制剂）处理时，染色体在特定位点（脆弱位点）断裂，这些位点与肿瘤细胞中观察到的易位断点相关。在 ATM 和 ATR 基因突变的哺乳动物细胞中也观察到高水平的染色体断裂和其他畸变。我们的总体目标是模拟酿酒酵母中的这种类型的遗传不稳定性，并表征造成这种不稳定性的机制。我们的具体目标是：1) 确定表征酵母脆弱位点的 DNA 序列特性，并表征与脆弱位点 DNA 断裂相关的染色体重排，2) 表征具有影响 DNA 损伤的基因突变的酵母菌株中的染色体畸变检查点、端粒长度调节、重组和/或染色质组装；例如，将检查具有 mec1 和/或 tel1 基因（分别是哺乳动物 ATR 和 ATM 基因的酵母同源物）的菌株，以及 3）了解电离辐射引起的遗传不稳定性。这些研究将强调能够检查整个酵母基因组的技术，包括 DNA 微阵列分析（检测基因剂量的变化并绘制易位断点图），以及能够分离完整染色体 DNA 分子的凝胶技术。