Mechanisms linking replication stress to genome instability in fission yeast

基因组不稳定指的是影响染色体序列、结构或数量的变化 细胞功能正常。这种不稳定性是癌症的特征，以及某些发育和 神经缺陷和衰老。来自多个生物体的数据表明，DNA复制压力是一种 基因组不稳定的关键因素。稳定复制分叉、防止异常的机制 分裂和促进DNA修复是疾病的主要障碍；因此，理解他们的 它们的功能及其破坏的后果与人类健康直接相关。 这项提议采用了一种已建立的细胞生物学模型系统，即分裂酵母S.pombe， 研究活细胞如何应对复制压力。S.pombe是一种公认的遗传基因 染色体生物学模型，具有许多与人类细胞相同的特征。值得注意的是，几乎所有的 正在研究的基因在人类中具有与疾病相关的同源基因。 该方法的一个关键方面是使用活细胞成像来表征对 复制应激并描述其长期后果。最重要的目标是理解 正常和突变细胞中复制应力的动态变化及其解决方法。这包括 确定细胞如何部署分子机制以允许损害解决并确保 染色体分离。我们在以下条件下解决了分裂的细胞和遗传后果 应激；调查复制如何在G2后期或有丝分裂中发生以促进解决；以及检查 维修结构的立体组织。我们之前已经证明，近着丝点 是一个脆弱的位置，我们已经扩展了它来检查核糖体DNA和时相的作用 分离有助于基因完整性，以及识别其他脆弱区域。一本小说 是对减数分裂过程中复制应力作为染色体贡献者的分析 与出生缺陷和不孕不育相关的重组。 通过将这种细胞生物学方法与出色的酵母基因发现工具相结合，以及 确定导致异常分裂和进一步压力的分子事件，这个项目解决了一个 当前认识上的严重差距。导致不同反应的途径是什么 压力及其相关的病理，以及它们如何影响活细胞的生物学？一起， 这些研究提供了保守蛋白质如何相互作用以维持基因组稳定的整体图景。 在真核细胞中，识别人类疾病的标记和风险因素。

Genome instability refers to changes in chromosome sequence, structure, or number that affect normal cell function. Such instability is characteristic of cancer, as well as certain developmental and neurological defects, and aging. Data from multiple organisms suggests that DNA replication stress is a key contributor to genome instability. Mechanisms that stabilize replication forks, prevent abnormal divisions, and promote DNA repair are a primary barrier to disease; therefore, understanding their function and the consequences of their disruption has direct relevance to human health. This proposal employs an established model cell biology system, the fission yeast S. pombe, to characterize how living cells respond to replication stress. S. pombe is a well-established genetic model for chromosome biology that shares many features with human cells. Significantly, nearly all the genes under study have orthologues in humans that have been associated with disease.. A key aspect of the approach is to use live cell imaging to characterize the response to replication stress and characterize its long term consequences. The overarching goal is to understand the dynamics of replication stress and its resolution in normal and mutant cells. This includes determining how the cell deploys molecular mechanisms to allow damage resolution and ensure chromosome segregations. We address the cellular and genetic consequences of division under stress; investigate how replication occurs late in G2 or mitosis to facilitate resolution; and examine the three-dimensional organization of repair structures. We have previously shown that the pericentromere is a fragile site, and we have expanded that to examine the ribosomal DNA and the role of phase separation in contributing to gene integrity, as well as identification of other fragile regions. A novel component is the analysis of replication stress during meiosis as a contributor to chromosome rearrangements associated with birth defects and infertility. By combining this cell biological approach with superb yeast gene-discovery tools, and identifying the molecular events that lead to abnormal divisions and further stress, this project tackles a critical gap in current understanding. What are the pathways that contribute to different responses to stress and their associated pathologies and how do they affect the biology of living cells? Together, these studies provide a holistic picture of how conserved proteins interact to maintain genome stability in a eukaryotic cell, identifying markers and risk factors for human disease.