DNA replication checkpoints in fission yeast

裂殖酵母中的 DNA 复制检查点

• 批准号: 7093040
• 负责人: GENNARO D'URSO
• 金额: $ 30.99万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7093040
• 关键词: DNA damage; DNA repair; DNA replication; DNA replication origin; Saccharomyces cerevisiae; Schizosaccharomyces pombe; cell cycle; gene expression; genetic screening; genetic transcription; microarray technology; molecular cloning; mutant; polymerase chain reaction; protein structure function; tissue /cell culture; two dimensional gel electrophoresis; yeasts

DESCRIPTION (provided by applicant)Understanding the mechanisms that result in increased genetic instability is of great interest to those studying the development of cancer. Inhibition of DNA replication can lead to increases in the frequency of gross chromosomal rearrangements (GCRs), that can arise from DNA damage associated with stalled or collapsed replication forks. In the yeast, Schizosaccharomyces pombe, cells activate specific checkpoint pathways in response to DNA damage, and these checkpoints are essential to allow time for repair. We have discovered a novel checkpoint phenotype associated with mutants in DNA replication initiation proteins called rid (for replication initiation defective). When grown under semi-permissive conditions, rid mutants are delayed in the cell cycle but fail to activate the inter-S phase checkpoint. However, these cells still require the checkpoint kinase Chk1 for viability, suggesting an alternative checkpoint is activated. We propose to investigate the nature of the damage generated in rid mutants and to identify checkpoint/repair proteins required for rid viability. To do this, we will employ both genetic screens and gene microarray analysis. We will also determine whether mutation rates, including the incidence of GCRS, increase in the rid or checkpoint mutants. The results of the proposed experiments should provide a much better understanding of checkpoint pathways that respond to defects in the initiation of DNA replication. Considering the conserved aspects of many of these processes, our experimental findings are likely to be applicable to higher eukaryotic cells, including human. Moreover, our results will likely identify new drug targets for cancer therapy, and reveal potentially less mutagenic strategies to block cell cycle progression in cancer cells.

描述（由申请人提供）理解导致遗传不稳定性增加的机制对研究癌症发展的人非常感兴趣。DNA复制的抑制可导致总染色体重排（GCR）频率的增加，其可由与停滞或塌陷的复制叉相关的DNA损伤引起。在酵母中，裂殖酵母菌，细胞激活特定的检查点途径来响应DNA损伤，这些检查点对于修复时间至关重要。我们已经发现了一种新的检查点表型与突变体的DNA复制起始蛋白称为rid（复制起始缺陷）。当在半允许条件下生长时，rid突变体在细胞周期中延迟，但不能激活S期间检查点。然而，这些细胞仍然需要检查点激酶Chk 1才能生存，这表明替代检查点被激活。我们建议调查的性质所产生的损坏的rid突变体，并确定检查点/修复蛋白所需的rid活力。为此，我们将采用基因筛选和基因微阵列分析。我们还将确定突变率，包括GCRS的发生率，是否在rid或检查点突变体中增加。拟议的实验的结果应该提供一个更好的理解检查点的途径，响应缺陷的DNA复制的启动。考虑到许多这些过程的保守方面，我们的实验结果可能适用于高等真核细胞，包括人类。此外，我们的研究结果可能会确定癌症治疗的新药物靶点，并揭示潜在的较少诱变策略来阻断癌细胞的细胞周期进程。