Admin. supplement for equipment to Mechanisms underlying the Rlm1-dependent G1 checkpoint (NIH R15 GM135807)

行政。

• 批准号: 10598250
• 负责人: SAUL M HONIGBERG
• 金额: $ 2.8万
• 依托单位: UNIVERSITY OF MISSOURI KANSAS CITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10598250
• 关键词: Biological Assay; Bypass; Cell Cycle; Cell Cycle Progression; Cell Cycle Regulation; Cell Cycle Stage; Cell Death; Cell Maintenance; Cell Wall; Cell division; Cell surface; Cells; Cellular Structures; Chromosomes; Cytology; Disease; Enzymes; Equipment; Event; Genes; Genetic; High-Risk Cancer; Lacazia loboi; Lead; Link; Malignant Neoplasms; Molecular; Morphology; Mutation; Names; Nature; Pathogenesis; Pathogenicity; Positioning Attribute; Proteins; Role; Signal Transduction; Stress; Structure; Testing; Time; United States National Institutes of Health; Work; Yeasts; anti-cancer therapeutic; cancer cell; cell injury; daughter cell; human pathogen; mutant; new therapeutic target; novel; parent grant; programs; repaired; response; transcription factor

(from parent grant) As cells divide the different cellular programs of cell division must be coordinated with one another. For example, the duplication of chromosomes, the separation of these duplicated chromosomes, and the division of one cell into two cells must all occur at precise times relative to one another and to other cellular events. To achieve this coordination, there are special times during the cell cycle, termed checkpoints, in which progression of the cell cycle can be paused. At these checkpoints, accurate/ undamaged completion of an earlier program is necessary before a later program will be initiated. Checkpoints work because the cell has specialized machines, made up of enzymes and other proteins, that are activated by damaged or incomplete cellular structures. Once activated these checkpoint machines cause the progression of the cell cycle to halt until the cellular structures are repaired and complete. When checkpoints are defective, cells continue through the cycle accumulating damaged structures and leading to disease states. Indeed, checkpoints are often bypassed in cancer cells, and defective checkpoints lead to higher risk of cancer. We recently proposed a novel checkpoint, here termed the “Rlm1-dependent checkpoint”, that delays passage through the cell cycle under a particular stressful environmental condition. As the name suggests, this checkpoint was revealed by a deletion mutant in the gene encoding the Rlm1 transcription factor. Rlm1 is known to be activated in response to cell-wall stress, so it may be that this checkpoint responds to stress at the cell surface. Interestingly, bypassing the Rlm1 checkpoint, unlike bypassing known checkpoints, leads to cell death in only one of the two products of cell division. Our long-term objective in this project is to characterize the function and mechanism of the Rlm1-dependent checkpoint. Our first specific aim is to characterize the position during the cell cycle at which this checkpoint operates, and the cell cycle regulators and additional cellular components through which it acts. Our second specific aim is to identify the nature of the signal to which this checkpoint responds and the nature of the damage that accumulates when the checkpoint is bypassed. To accomplish these aims we will employ a combination of genetic, cytological, and molecular biological assays. For example, we will grow both normal yeast and mutants defective in the Rlm1 checkpoint under non-stressful conditions and then release them suddenly into the stressful condition. We will then compare the normal and mutant yeast over time for known molecular or cellular events in the cell cycle as well as different types of cellular damage. We will test specific hypotheses regarding the mechanism of this checkpoint by examining mutants known to be defective in particular aspects of cell maintenance and cell cycle control for their role in this checkpoint. Characterization of this new type of checkpoint should reveal important new aspects of cell cycle control and may prove useful in understanding new aspects of disease states.

（来自家长补助） 当细胞分裂时，不同的细胞分裂程序必须相互协调。为了 例如，染色体的重复、这些重复染色体的分离以及 一个细胞分裂成两个细胞必须在相对于彼此和其他细胞的精确时间发生 事件。为了实现这种协调，细胞周期中有一些特殊的时间，称为检查点， 细胞周期的进展可以暂停。在这些检查点，准确/无损地完成 在启动较晚的计划之前，需要先执行较早的计划。检查点之所以起作用是因为 细胞有专门的机器，由酶和其他蛋白质组成，被损坏或损坏时激活 不完整的细胞结构。一旦激活这些检查点机器就会导致细胞的进展 循环停止，直到细胞结构修复并完成。当检查点有缺陷时，细胞 继续这个循环，累积受损的结构并导致疾病状态。的确， 癌细胞中的检查点经常被绕过，而有缺陷的检查点会导致更高的癌症风险。我们 最近提出了一种新颖的检查点，这里称为“Rlm1依赖检查点”，可以延迟通过 在特定的应激环境条件下经历细胞周期。顾名思义，这 检查点是由编码 Rlm1 转录因子的基因中的缺失突变体揭示的。 Rlm1 是 已知会响应细胞壁压力而被激活，因此该检查点可能对压力做出反应 细胞表面。有趣的是，与绕过已知检查点不同，绕过 Rlm1 检查点会导致 仅导致细胞分裂的两种产物之一的细胞死亡。我们在这个项目中的长期目标是 描述 Rlm1 依赖检查点的功能和机制。我们的第一个具体目标是 表征该检查点在细胞周期中运行的位置，以及细胞周期 调节器和其发挥作用的其他细胞成分。我们的第二个具体目标是确定 该检查点响应的信号的性质以及累积损坏的性质 当检查点被绕过时。为了实现这些目标，我们将结合遗传、 细胞学和分子生物学测定。例如，我们将种植正常酵母和突变体 在非压力条件下Rlm1检查点有缺陷，然后突然将它们释放到 紧张的状况。然后，我们将比较正常和突变酵母随时间的已知分子或 细胞周期中的细胞事件以及不同类型的细胞损伤。我们将具体测试 通过检查已知有缺陷的突变体来提出有关该检查点机制的假设 细胞维护和细胞周期控制的特定方面在这个检查点中的作用。 这种新型检查点的表征应该揭示细胞周期控制的重要新方面 并且可能有助于理解疾病状态的新方面。