Dissecting the genetic determinants of aneuploidy's effect on cellular proliferat

描述（由申请人提供）：异常核型，包括节段性和全染色体非整倍性，是癌症的标志。许多肿瘤是非整倍体，并且有证据表明非整倍体可能是肿瘤发生的驱动因素[27]。尽管与癌症有密切联系，但非整倍性与细胞周期延迟和生长速率降低相矛盾[25，29]。非整倍性导致数十至数千个基因的协同拷贝数变化。这种遗传复杂性使得人们很难理解非整倍体如何促进肿瘤发生和细胞增殖。酿酒酵母是一种研究充分的模式生物，其细胞生物学的许多元素与哺乳动物细胞保守。在S.由于酵母基因组的相对简单性和许多可用的菌株收集，因此酵母是酿酒酵母的主要来源。在一个与肿瘤发生有许多相似之处的过程中，我们的实验室分离出了S.酿酒酵母从一个子集的24个独立的长期进化实验[7]。正如假设癌细胞群体中经常出现的非整倍体与增殖优势相关[17]，同样，在目标1中，我们计划鉴定从这些进化实验中分离的高频非整倍体克隆，并在目标2中确定其增殖优势。群体水平的进化实验的分析将进行使用阵列比较基因组杂交（aCGH）的群体DNA，而不同菌株的相对增殖优势将通过直接竞争实验来确定。在目标3中，我们将利用跨越超过90%的蛋白质编码基因组的条形码酵母集合[10，30]和新型高通量测序技术Bar-seq [21]来确定非整倍体区域内多个基因的协调拷贝数变化如何组合影响细胞增殖。我们希望本文提出的对非整倍体的严格遗传分析将有助于我们更好地理解非整倍体在肿瘤发生和癌症进展中的作用。

DESCRIPTION (provided by applicant): An abnormal karyotype, including both segmental and whole chromosomal aneuploidies, is a hallmark of cancer. Many tumors are aneuploidy and there is evidence that aneuploidy may be a driver of tumorigenesis [27]. Despite these close ties to cancer, aneuploidy is paradoxically associated with a cell cycle delay and decreased growth rates [25, 29]. Aneuploidy results in the coordinated copy-number change of tens to thousands of genes. This genetic complexity has made it difficult to understand how aneuploidy might promote tumorigenesis and cellular proliferation. Saccharomyces cerevisiae is a well-studied model organism with many elements of its cellular biology conserved with mammalian cells. The study of complex genetic problems is simplified in S. cerevisiae due to the relative simplicity of the yeast genome and by the many available strain collections. In a process with many parallels to tumorigenesis, our laboratory has isolated aneuploid clones of S. cerevisiae from a subset of 24 independent long-term evolution experiments [7]. Just as aneuploidies frequently represented in a population of cancer cells are hypothesized to be associated with a proliferative advantage [17], similarly, in Aim 1 we plan to identify high-frequency aneuploid clones isolated from these evolution experiments and in Aim 2 determine their proliferative advantage. Population-level analysis of the evolution experiments will be carried out using array comparative genomic hybridization (aCGH) of population DNA while the relative proliferative advantage of different strains will be determined by direct competition experiments. In Aim 3 we will exploit bar-coded yeast collections spanning more than 90% of the protein coding genome [10, 30] and the novel high-throughput sequencing technology Bar-seq [21] to determine how the coordinated copy- number change of multiple genes within an aneuploid region combines to affect cellular proliferation. We hope that the rigorous genetic analysis of aneuploidy proposed here will help us better understand the role of aneuploidy in tumorigenesis and cancer progression.