Characterization of JNK in Cell Cycle Control

JNK 在细胞周期控制中的表征

• 批准号: 7676182
• 负责人: Ze'ev A Ronai
• 金额: $ 39.63万
• 依托单位: SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-19 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7676182
• 关键词: Address; Affect; Animal Model; Biochemical; Boxing; Cell Cycle; Cell Cycle Arrest; Cell Cycle Checkpoint; Cell Cycle Progression; Cell Cycle Regulation; Cell Death; Cells; Cellular Stress Response; Cellular biology; Chromosomal Instability; Collaborations; Cultured Cells; Cyclin B; DNA Damage; DNA damage checkpoint; Data; Equilibrium; Exhibits; Family; Family member; Foundations; G1 Phase; G2/M Arrest; Generations; Genetic; Genetic Models; Genotoxic Stress; Human; Human Development; In Vitro; JNK-activating protein kinase; Knock-in Mouse; Link; Lobe; MAPK8 gene; MAPK9 gene; Malignant Neoplasms; Mammalian Cell; Mediating; Meiosis; Microtubules; Mitosis; Mitotic spindle; Modeling; Molecular; Mus; Mutant Strains Mice; Oocytes; Pathway interactions; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases; Physiological; Play; Protein Isoforms; Protein Kinase; Proteins; Recruitment Activity; Regulation; Role; Scaffolding Protein; Stress; System; Testing; Ubiquitination; Xenopus laevis; anaphase-promoting complex; base; biological adaptation to stress; cytokine; genetic analysis; genetic regulatory protein; in vivo; melanoma; member; mouse model; multicatalytic endopeptidase complex; novel; public health relevance; reconstitution; response; segregation; stress activated protein kinase; tumor; ubiquitin ligase; ultraviolet irradiation

DESCRIPTION (provided by applicant): JNK (1-3) are members of the stress-activated protein kinase family that regulates the cellular stress response via their control of cell death and survival. Our recent studies disclose an unexpected mechanism for the regulation and consequently the function of JNK; our preliminary results demonstrate that through its KEN-box, JNK is targeted for degradation in a cell cycle-dependent manner. Such targeting is mediated by Cdh1, which recruits the Anaphase Promoting Complex or Cyclosome (APC/C) ubiquitin ligase to ubiquitinate JNK, resulting in its proteasome-dependent degradation. APC/CCdh1-mediated JNK degradation primarily occurs during the exit from mitosis, and G1 phases of the cell cycle. Our preliminary data also identify Cdc25C as JNK substrate at the G2/M-G1 phases of the cell cycle. JNK degradation is important for the regulation of Cdc25C activity and Wee1 stability. Thus, a non-degradable (yet which can be activated) form of JNK (JNKKEN) induces reduced cyclin-B/Cdk1 activity, affects spindle and chromosomal dynamics and delays exit from mitosis. These findings provide the foundation for our hypothesis that through the regulation of Cdc25C, JNK plays an important role in control of cell cycle progression during which it is tightly regulated by the APC/CCdh1. Our finding that JNK is a cell cycle regulator offers an undisclosed link between JNK and unrestrained cell cycle progression as well as chromosome instability, commonly observed in human cancers, where the balance between JNK functions as a stress kinase and cell cycle control protein might be altered. To test our hypothesis we propose to carry out the following studies: Aim 1 - Assess the molecular determinants responsible for JNK activity during the cell cycle and determine which of JNK family members is most important for cell cycle control.; Aim 2- characterize the effect of JNK on Cdc25C as part of its control of cell cycle transition. Aim 3 -Characterize the cytological changes in mitosis that are controlled by JNK and Cdc25C regulation by JNK; Aim 4 - determine the physiological significance of JNK's role in cell cycle control in a JNK-KEN knock-in mouse model. Aim 5 - using genetic, biochemical and cell biology approaches, determine the role of JNK in cell cycle checkpoint pathways following stress and DNA damage and in human melanoma as a model for constitutively deregulated JNK activity. This proposal brings together experts that closely collaborate to address an important and novel function of the key kinase, JNK. This concerted effort will provide the foundation for understanding the role of JNK in cell cycle progression and the implication of its deregulated control to genotoxic stress response as well as to development of human cancer. PUBLIC HEALTH RELEVANCE: This application will test the hypothesis that JNK is important player in cell cycle control prior and more so, in response to DNA damage. Support for this hypothesis comes from studies in which we discovered that JNK is targeted for degradation at G2M-G1 phases of the cell cycle. JNK mediates its function through phosphorylation of Cdc25C which affects its phosphatase activity. Interfering with JNK degradation or altering its activity delays exit from mitosis and impairs G2 arrest after DNA damage. Using biochemical, cellular and genetic models our proposed studies will delineate the requirements and regulation of this newly identified regulatory lobe along the cell cycle and DNA damage response.

描述（由申请人提供）：JNK（1-3）是应激激活蛋白激酶家族的成员，可通过控制细胞死亡和生存来调节细胞应激反应。我们最近的研究揭示了对调节的意外机制以及JNK的功能。我们的初步结果表明，通过其KEN-box，JNK以细胞周期依赖性方式降解。这种靶向是由CDH1介导的，CDH1募集了促进复合物或循环体（APC/C）泛素连接酶的泛素蛋白JNK的泛素蛋白依赖性降解。 APC/CCDH1介导的JNK降解主要发生在有丝分裂的退出期间，而细胞周期的G1阶段。我们的初步数据还将CDC25C识别为细胞周期G2/M-G1阶段的JNK底物。 JNK降解对于调节CDC25C活性和WEE1稳定性很重要。因此，JNK（JNKKEN）的不可降解（但可以激活）形式会诱导细胞周期蛋白-B/CDK1活性的降低，会影响纺锤体和染色体动力学，并延迟有效性。这些发现为我们的假设奠定了基础，即通过调节CDC25C，JNK在控制细胞周期进程中起着重要作用，在此过程中，它受APC/CCDH1严格调节。我们的发现，JNK是一种细胞周期调节剂，在人类癌症中通常观察到JNK与不受约束的细胞周期进展以及染色体不稳定性之间的未公开联系，其中JNK在JNK之间作为应激激酶和细胞周期控制蛋白的平衡可能会改变。为了检验我们的假设，我们建议进行以下研究：目标1-评估在细胞周期期间负责JNK活​​性的分子决定因素，并确定JNK家族成员的哪个对细胞周期控制最重要。 AIM 2-将JNK对CDC25C的影响作为其控制细胞周期转变的一部分。 AIM 3-将JNK控制和CDC25C调控控制的有丝分裂细胞学变化； AIM 4-确定JNK在JNK ken敲入小鼠模型中JNK在细胞周期控制中的作用的生理意义。 AIM 5-使用遗传，生化和细胞生物学方法，确定JNK在压力和DNA损伤后以及人类黑色素瘤中的JNK在细胞周期检查点途径中的作用，作为组成性放松管制的JNK活性的模型。该建议将专家汇集在一起​​，这些专家紧密合作，以解决关键激酶JNK的重要和新颖功能。这项一致的努力将为理解JNK在细胞周期进程中的作用以及其失控控制对遗传毒性应激反应以及人类癌症发展的影响提供基础。公共卫生相关性：该应用将检验以下假设：JNK是先前的细胞周期控制中的重要参与者，而对于DNA损害的响应。对这一假设的支持来自于研究，我们发现JNK的目标是在细胞周期的G2M-G1阶段降解。 JNK通过影响其磷酸酶活性的Cdc25c的磷酸化来介导其功能。干扰JNK降解或改变其活性延迟从有丝分裂中退出并损害DNA损伤后G2停滞。使用生化，细胞和遗传模型，我们提出的研究将描绘出沿细胞周期和DNA损伤响应的新鉴定的调节叶的要求和调节。