CELL CYCLE CHECKPOINT CONTROL IN RESPONSE TO DNA DAMAGE

针对 DNA 损伤的细胞周期检查点控制

• 批准号: 2192499
• 负责人: NANCY C WALWORTH
• 金额: $ 19.42万
• 依托单位: UNIV OF MED/DENT NJ-R W JOHNSON MED SCH
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2192499
• 关键词: DNA damage; SDS polyacrylamide gel electrophoresis; biological signal transduction; cell cycle; cell cycle proteins; enzyme activity; gel filtration chromatography; gel mobility shift assay; gene mutation; immunoprecipitation; phosphorylation; protein kinase; protein structure function; site directed mutagenesis; yeasts

The presence of a mechanism which monitors the integrity of the genome and leads to cell cycle arrest in the event of DNA damage has been described as checkpoint control. Failure to arrest the cell cycle when DNA is damaged can lead to the propagation of mutations or loss of chromosomal material. While the phenomena of cell cycle arrest before DNA replication (G1 arrest) or after DNA replication (G2 arrest) is well- established, the signal transduction pathway which couples the detection of DNA damage to control of progression through the cell cycle is only beginning to be elucidated. The proposed project aims to characterize the checkpoint which leads to cell cycle arrest prior to mitosis in response to DNA damage, initially through the characterization of the chk1 protein kinase (p56chk1) in Schizosaccharomyces pombe. Cells which lack a functional chk1 gene fail to arrest the cell cycle prior to mitosis when DNA damage takes place, attempt to proceed through the cell cycle with damaged DNA and subsequently die. The products of several other genes are also required for cell cycle arrest in response to DNA damage; however, despite knowledge of the primary sequence of the rad gene products, little is known about their function. As a protein kinase, p56chk1 is an ideal protein with which to initiate a mechanistic characterization of this pathway. To determine the role of p56chk1 in mediating cell cycle arrest following DNA damage, two complementary lines of research will be carried out: biochemical studies to characterize the regulation of the activity of p56chk1 and genetic screens to identify proteins with which p56chk1 interacts. The fission and budding yeasts have been used successfully as tools for the identification of human genes which govern progression through the cell cycle due to evolutionary conservation of the molecules involved. The architecture of many signal transduction pathways has been conserved as well. Thus, characterization of the p56chk1 dependent cell cycle arrest pathway should prove to be a useful paradigm for dissecting the pathway coupling detection of DNA damage to cell cycle arrest in human cells. Information regarding the mechanism of cell cycle arrest will be vital for the design of more effective ways of overriding the pathway for chemotherapeutic treatment of tumor cells.

存在一种监测基因组完整性的机制 并在DNA损伤的情况下导致细胞周期停滞， 称为检查点控制。未能阻止细胞周期， DNA受损会导致突变的传播或基因的丢失。 染色体物质虽然细胞周期停滞现象在DNA 复制（G1停滞）或DNA复制后（G2停滞）是很好的- 建立了与检测偶联的信号转导通路， 控制细胞周期进程的DNA损伤 开始被阐明。拟议的项目旨在描述 在有丝分裂之前导致细胞周期停滞的检查点 DNA损伤，最初是通过chk 1蛋白的表征， 裂殖酵母p56 chk 1激酶。细胞缺乏 功能性chk 1基因不能在有丝分裂前阻止细胞周期， DNA损伤发生，试图通过细胞周期进行， DNA受损，然后死亡。其他几个基因的产物是 也是响应DNA损伤的细胞周期停滞所需的;然而， 尽管已知RAD基因产物的一级序列， 关于它们的功能知之甚少。作为一种蛋白激酶，p56 chk 1是一种蛋白激酶。 理想的蛋白质，用其启动 这条路。探讨p56 chk 1在细胞周期调控中的作用 DNA损伤后的逮捕，两个互补的研究路线将是 进行了：生化研究，以确定 p56 chk 1的活性和遗传筛选，以鉴定 p56 chk 1相互作用。 分裂和芽殖酵母已成功地用作 确定人类基因，这些基因控制着通过 细胞周期由于进化保守的分子参与。 许多信号转导通路的结构是保守的 也因此，p56 chk 1依赖性细胞周期的表征 逮捕途径应该被证明是剖析大脑的一个有用的范式。 细胞周期阻滞的DNA损伤途径偶联检测 细胞关于细胞周期阻滞机制的信息将在 对于设计更有效的方法来覆盖 肿瘤细胞的化学治疗。