Inhibition of DNA re-replication by cyclin/CDK and GSK-3 kinase in S. cerevisiae

酿酒酵母中细胞周期蛋白/CDK 和 GSK-3 激酶对 DNA 再复制的抑制

• 批准号: 9040204
• 负责人: Amy E Ikui
• 金额: $ 11.78万
• 依托单位: BROOKLYN COLLEGE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9040204
• 关键词: Address; Amino Acid Sequence; Bacteria; Biochemical; Biological Assay; Cell Cycle; Cell physiology; Chromosomal Instability; Chromosomes; Complex; Consensus; Cyclin-Dependent Kinases; Cyclins; DNA; DNA Replication Factor; DNA biosynthesis; Development; Ensure; Eukaryota; Eukaryotic Cell; Failure; Future; Genetic Epistasis; Genomic Instability; Glycogen Synthase Kinase 3; Goals; Health; Human; In Vitro; Investigation; Knowledge; Lead; Licensing; Life; Link; Mediating; Molecular; Mutation; N-terminal; Organism; Outcomes Research; Phosphorylation; Phosphotransferases; Prevention; Protein Kinase; Proteins; Recombinants; Replication-Associated Process; Role; Saccharomyces cerevisiae; Saccharomycetales; Site; System; Testing; Time; Ubiquitination; Yeasts; base; cancer therapy; college; conditional mutant; design; genome integrity; inhibitor/antagonist; innovation; mutant; novel; research study; therapeutic target; tumorigenesis; ubiquitin-protein ligase; yeast genetics

DESCRIPTION (provided by applicant): Eukaryotic cells duplicate their chromosomes. Errors in the DNA replication control could lead to chromosome instability. Our long-term goal is to understand the molecular mechanism of DNA replication control in eukaryotes. Cdc6p is a key DNA replication component from yeast to humans. Our preliminary results showed that yeast GSK-3 kinase (Mck1p) targets DNA replication factor Cdc6p for degradation, which in turn inhibits DNA re-replication. It is known that N-terminal region of Cdc6 is phosphorylated by Cyclin/CDK complex for its degradation after the origin is licensed. We will study the novel Cdc6p degradation mechanism controlled by Mck1p kinase to inhibit DNA re- replication. In this proposal, three aims will test my hypothesis if a sequential phosphorylation of Cdc6p by Cdk1 and GSK3 controls the timing of Cdc6p degradation. Aim1 will test if Cdc6p is directly phosphorylated by Mck1 kinase, and Mck1-depedent Cdc6 degradation is mediated through SCFCDC4 complex. Aim2 will test the possibility that Mck1p targets Cdc6p in a distinct mechanism from CDK. Aim3 will test if the phosphorylation of Cdc6 by CDK is a pre-requisite for phosphorylation by Mck1p. Cdc6p and GSK-3 kinase are conserved from yeast to humans. The results obtained from this study can be applied to understand the molecular mechanism of Cdc6 degradation by GSK-3 kinase in higher eukaryotes. The accurate DNA replication control is a critical step to avoid chromosome instability, and it is important to understand since the chromosome instability is a hallmark of tumorigenesis.

描述(申请人提供)：真核细胞复制它们的染色体。DNA复制控制中的错误可能会导致染色体不稳定。我们的长期目标是了解真核生物中DNA复制控制的分子机制。CDC6P是从酵母到人类的关键DNA复制组件。我们的初步结果表明，酵母GSK-3激酶(Mck1p)靶向DNA复制因子CDC6p的降解，这反过来又抑制DNA的重新复制。已知CDC6的N-末端区域被Cyclin/CDK复合体磷酸化，使其在来源许可后被降解。我们将研究Mck1p激酶控制的新的CDC6P降解机制，以抑制DNA的重新复制。在这个提议中，有三个目标将检验我的假设，即CDK1和GSK3对CDC6P的顺序磷酸化是否控制了CDC6P降解的时间。AIM1将检测CDC6p是否被Mck1激酶直接磷酸化，而Mck1抑制的CDC6降解是通过SCFCDC4复合体介导的。AIM2将测试Mck1p以不同于CDK的机制靶向CDc6p的可能性。Aim3将测试CDK对CDC6的磷酸化是否是Mck1p磷酸化的先决条件。CDC6P和GSK-3激酶从酵母到人类都是保守的。本研究结果可用于理解高等真核生物中GSK-3激酶降解CDC6的分子机制。准确的DNA复制控制是避免染色体不稳定性的关键步骤，了解染色体不稳定性是肿瘤发生的一个标志，因此了解染色体不稳定性是非常重要的。