Analysis of the Roles of Genes and Chromosome Rearrangements in Genomic..

摘要 这项研究的长期目标是了解基因组不稳定性的分子基础及其在 癌症。这项建议中的三个目标是由我们先前的研究[1]和最近发表的一项 对哺乳动物癌细胞的研究。我们已经使用了模式生物酿酒酵母(萌芽 酵母)开发一种特定的染色体分析系统(在本提案中称为chrivii系统)。我们 以前使用这个系统识别了一个新的不稳定染色体位置(脆性位置)，当 不稳定导致不稳定的染色体中间体的形成。我们已经确定了关键基因的作用 并建立了解释其不稳定性的工作模型。在这份提案中， 我们首先将继续确定稳定特定不稳定部位所需的基因和遗传途径， 同时使用候选基因和全基因组遗传筛选。第二，我们将在基因上识别出其他 酵母基因组中不稳定的位置，这将导致对多条染色体的理解 导致不稳定的决定因素。第三，我们将检验一个假设，解释为什么染色体不稳定 中间体不稳定。这一假说部分是由最近在癌细胞中观察到的 告诉我们，不稳定的染色体很常见，原因未知，但可能是重要的原因，在 酵母和哺乳动物细胞(因此可能存在于所有细胞类型)。这三个目标中的每一个都与 癌症研究，每一个都在技术上要求足够高，除了最详细的研究 复杂的模型生物充其量也是笨拙的。萌芽酵母有一种复杂而又容易 被操纵的基因组，因此对执行所提出的具有一般性的实验是有用的 染色体生物学与癌症的相关性。该项目还将提供一个极好的教育和 为美洲原住民学生提供癌症生物学方面的培训工具，因此将为实现 美洲原住民癌症预防伙伴关系以减轻不平等的癌症负担 印第安人。

ABSTRACT The long term goal of this study is to understand the molecular basis of genomic instability and its role in cancer. The three aims in this proposal are motivated by our previous study [1] and from a recently published study in mammalian cancer cells. We have used the model organism Saccharomyces cerevislae (budding yeast) to develop a specific chromosome assay system (referred to as the ChrVII system in this proposal). We have previously used this system to identify a novel unstable chromosome site (a fragile site) that when unstable leads to the formation of unstable chromosome intermediates. We have identified roles of key genes in stability of the fragile site, and have developed a working model that explains its instability. In this proposal, we first will continue to identify genes and genetic pathways required to stabilize the specific unstable site, using both a candidate gene and a genome wide genetic screen. Second, we will identify additional genetically unstable sites in the yeast genome, which will lead to an understanding of the multiple chromosomal determinants that cause instability. Third, we will test one hypothesis for why unstable chromosome intermediates are unstable. This one hypothesis is motivated in part by recent observations in cancer cells that suggest to us that unstable chromosomes are common, for unknown but potentially important reasons, in yeast and in mammalian cells (and thus probably in all cell types). Each of these three aims is of interest in cancer research, and each is technically demanding enough that detailed study in all but the most sophisticated model organisms is cumbersome at best. Budding yeast has a sophisticated yet easily manipulated genome, and as such is useful to carry out the experiments proposed that are of general relevance in chromosome biology and cancer. This project will also provide an excellent educational and training vehicle for Native American students in cancer biology, and thus will contribute strongly to the goals of The Partnership for Native American Cancer Prevention to alleviate the unequal burden of cancer among Native Americans.