Identification of Yeast Chromosome Condensation Factors

描述（由申请人提供）染色体精确分离所需因子的失调可导致非整倍体，这是癌症病因学的重要贡献者。复制基因组的均等分裂需要姐妹染色单体在后期迁移到有丝分裂纺锤体的两极：分离的精确性依赖于精细的机制，并依赖于正确的染色体组织。参与染色体凝聚和基因组有机化的因素对于维持基因组稳定性也至关重要。基因组不稳定性和非整倍体是恶性进展的关键因素。参与染色体结构的已知蛋白质在人类和芽殖酵母之间是高度保守的（S。cerevisiae）。然而，在这些过程中涉及的许多因素仍然是孤立的。由于酵母在遗传上是易处理的，它们提供了理想的系统，在其中可以快速鉴定细胞过程所需的新因子。我们的目标是识别和了解新的芽殖酵母蛋白，通过细胞周期控制染色体组织和结构的动态。我们的假设是，这些蛋白质的人类同源物将需要保持染色体分离的保真度和基因组的完整性。因此，这些因素将与癌症的病因学有关。 酵母遗传筛选将用于分离染色体浓缩缺陷的新突变体。两个绿色荧光蛋白（GFP）标记的染色体基因座，由约10 - 50个DNA内切酶分开，在酵母细胞中显示为单个离散荧光信号。然而，影响染色体凝聚状态的突变体将允许标记的基因座通过荧光显微镜彼此辨别。其他表型，如信号强度降低，也预期在许多缩合突变体。基于这些表型，将通过目视检查以及自动显微镜和计算机辅助诊断的组合来鉴定影响染色体组织的突变体。

DESCRIPTION (provided by applicant) Deregulation of factors needed for accurate chromosome segregation can result in aneuploidy, a significant contributor to cancer etiology. Equal division of a replicated genome requires that sister chromatids migrate to opposite poles of the mitotic spindle in anaphase: segregation fidelity relies on elaborate mechanics and is dependent on proper chromosome organization. Factors involved in chromosome condensation and genome orgatization are also critical for maintaining genome stability. Together, genome instability and aneuploidy are key factors in malignant progression. Known proteins involved in chromosome architecture are highly conserved between humans and budding yeast (S. cerevisiae). However, many factors involved in these processes remain to be isolated. Since yeasts are genetically tractable, they provide ideal systems in which novel factors required for cellular process can be rapidly identified. Our goal is to identify and understand new budding yeast proteins that control the dynamics of chromosome organization and structure through the cell cycle. Our hypothesis is that human homologs of these proteins will be required to maintain the fidelity of chromosome segregation and the integrity of the genome. These factors will therefore be relevant to the etiology of cancer. Yeast genetic screens will be used to isolate novel mutants defective in chromosome condensation. Two green fluorescent protein (GFP)-tagged chromosome loci, separated by -10-50 kilobases of DNA are visualized as a single discrete fluorescence signal in yeast cells. However, mutants that affect chromosome condensation states will allow the tagged loci to be discerned from one another by fluorescence microscopy. Other phenotypes, such as reduced signal intensity, are also expected in many condensation mutants. Based on these phenotypes, mutants affecting chromosome organization will be identified, both by visual inspection and a combination of automated microscopy and computer-aided diagnosis.