Genetic regulation of genome stability in yeast

酵母基因组稳定性的遗传调控

基本信息

批准号：
10646337
负责人：
THOMAS PETES
金额：
$ 70.69万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-01 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10646337
关键词：
ATR gene Accounting Aneuploidy Base Composition Biological Models Cells Centromere Chromosomes Cytosine DNA DNA Polymerase III DNA Repair DNA biosynthesis Data Deamination Enzymes Event Familial colorectal cancer GC gene Genes Genetic Genetic Nondisjunction Genetic Recombination Genome Genome Stability Genomic Instability Goals Guanine + Cytosine Composition Histone H2A Human Induced Mutation Maps Meclp Microsatellite Instability Mismatch Repair Modeling Molecular Chaperones Mutation Normal Cell Phenotype Phosphorylation Proteins Regulation Research Saccharomyces cerevisiae Single-Stranded DNA System TEL1 Gene Tandem Repeat Sequences Testing Yeasts ataxia telangiectasia mutated protein base cancer cell carcinogenesis causal variant experimental study neoplastic cell novel replication stress success telomere tumor yeast protein

项目摘要

Abstract Multiple genetic changes are necessary to convert a normal cell into a cancer cell. With a few exceptions, the mutations or conditions (for example, DNA replication stress) that initiate genetic instability and tumor formation are not understood. The goal of the proposed research is to use the yeast Saccharomyces cerevisiae as a model for investigating the mechanisms that generate the various types of genetic instability related to carcinogenesis. As an example of the success of this approach, our demonstration that DNA mismatch repair mutations in yeast produced the same rate of microsatellite instability observed in hereditary colorectal cancer cells was an important clue as to the causal mutation. 1. One of the proposed studies is the characterization of a novel mutator that is responsive to base composition. We showed that a gene with high GC content had a much-elevated mutation rate than genes with lower GC contents. We subsequently identified a mutation (met18) that elevated the mutation rate of a high-GC gene more than 100-fold, with a much smaller effect on other genes. The Met18 protein is a chaperone involved in the transport of Fe-S clusters into a variety of enzymes involved in DNA replication and DNA repair. Our current data suggest that DNA polymerase delta lacking the Fe-S cluster has substantially reduced processivity, accounting for the mutator phenotype of met18. This hypothesis will be tested by our proposed experiments. 2. Fusions between centromeres are commonly observed in tumor cells. We have developed a genetic system that allows the identification of recombination events occurring between the centromeres of different yeast chromosomes. We will use this system to examine the genetic regulation of centromere-centromere recombination. 3. We have recently used the mammalian APOBEC protein, which deaminates cytosine in single-stranded DNA, to map regions of single- stranded DNA in yeast cells undergoing DNA replication stress. Using APOBEC-induced mutations, we propose extending our studies to map deletions and duplications in arrays of tandemly-repeated genes. Such alterations are an important cause of genome instability. 4. Lastly, the Tel1p and Mec1p yeast proteins are related functionally to the human ATM and ATR proteins, respectively. Mutations in both human genes are associated with certain classes of tumors. Yeast cells with tel1 mec1 mutations have greatly elevated rates of chromosome rearrangements and chromosome non-disjunction. The chromosome rearrangements, but not the aneuploidy, are a consequence of a high rate of telomere fusions. We are testing the hypothesis that the high level of chromosome non-disjunction is a consequence of defective phosphorylation of histone H2A in tel1 mec1 strains.

抽象的需要多种遗传变化来将正常细胞转化为癌细胞。有几个例外，突变或条件（例如，DNA复制应力）启动遗传不稳定性和肿瘤形成尚不清楚。拟议的研究的目的是使用酵母糖疗法酿酒酵母作为研究产生各种遗传不稳定性的机制的模型与癌变有关。作为这种方法成功的一个例子，我们证明了DNA 酵母中的不匹配修复突变产生了与遗传性相同的微卫星不稳定性速率结直肠癌细胞是因果突变的重要线索。 1。拟议的研究之一是对基础成分有响应的新型突变器的表征。我们证明了一个高的基因 GC含量比具有较低GC含量的基因具有较高的突变率。随后我们确定了一个突变（MET18），将高-GC基因的突变率升高超过100倍，较小得多对其他基因的影响。 Met18蛋白是参与Fe-S簇转运到一种品种的伴侣涉及DNA复制和DNA修复的酶。我们当前的数据表明DNA聚合酶三角洲缺乏Fe-S簇的过程大大降低，这是MET18的突变器表型的解释。该假设将通过我们提出的实验来检验。 2。丝粒之间的融合通常是在肿瘤细胞中观察到。我们已经开发了一个遗传系统，可以鉴定重组发生的事件发生在不同酵母染色体的中心粒之间。我们将使用此系统检查着丝粒中心重组的遗传调节。 3。我们最近使用了哺乳动物Apobec蛋白，将单链DNA中的胞嘧啶脱氨酸以绘制单个单个区域经历DNA复制应激的酵母细胞中的滞留DNA。使用APOBEC诱导的突变，我们提议扩展我们的研究以绘制串联重复基因阵列的缺失和重复。这样的改变是基因组不稳定性的重要原因。 4。最后，TEL1P和MEC1P酵母蛋白是分别与人类ATM和ATR蛋白质有关。两个人类基因的突变是与某些类别的肿瘤相关。具有Tel1 Mec1突变的酵母细胞的速率大大提高染色体重排和染色体非分离。染色体重排，但没有非整倍性是高端粒融合率的结果。我们正在检验以下假设染色体非分离水平是Tel1组蛋白H2A磷酸化缺陷的结果 MEC1菌株。

项目成果

期刊论文数量（11）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Nanopore sequencing of complex genomic rearrangements in yeast reveals mechanisms of repeat-mediated double-strand break repair.

DOI：
10.1101/gr.228148.117
发表时间：
2017-12
期刊：
Genome research
影响因子：
7
作者：
McGinty RJ;Rubinstein RG;Neil AJ;Dominska M;Kiktev D;Petes TD;Mirkin SM
通讯作者：
Mirkin SM

Ribodysgenesis: sudden genome instability in the yeast Saccharomyces cerevisiae arising from RNase H2 cleavage at genomic-embedded ribonucleotides.

DOI：
10.1093/nar/gkac536
发表时间：
2022-07-08
期刊：
NUCLEIC ACIDS RESEARCH
影响因子：
14.9
作者：
Sui, Yang;Epstein, Anastasiya;Dominska, Margaret;Zheng, Dao-Qiong;Petes, Thomas D.;Klein, Hannah L.
通讯作者：
Klein, Hannah L.

Splitting the yeast centromere by recombination.