Chemical Genetic Studies of Mitosis

有丝分裂的化学遗传学研究

• 批准号: 6739674
• 负责人: RANDALL W KING
• 金额: $ 30.1万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6739674
• 关键词: Xenopus; acid aminoacid ligase; affinity chromatography; cell cycle; cell free system; cell growth regulation; chemical structure function; cyclins; high throughput technology; inhibitor /antagonist; intermolecular interaction; molecular genetics; paclitaxel; protein degradation; protein purification; reporter genes; ubiquitin

DESCRIPTION (provided by applicant): The goal of our research program is to understand how exit from mitosis is regulated in vertebrate cells and how this process is disrupted in cancer cells. Progression through the eukaryotic cell cycle is controlled by carefully timed protein phosphorylation and protein degradation. Anaphase and mitotic exit depend on the ubiquitin-dependent degradation of regulators such as securins and mitotic cyclins. These proteins are targeted for ubiquitination by a multisubunit ubiquitin ligase called the Anaphase-Promoting Complex or Cyclosome (APC). Our goal is to study how APC is controlled in vertebrate cells by finding chemicals that affect the regulation or activity of this complex. We have identified several compounds that stabilize cyclin B in Xenopus egg extracts and block exit from mitosis through a novel mechanism. Our goal is to identify the protein targets of these inhibitors using a combination of biochemical characterization and affinity-based techniques. We have also identified a compound that directly inhibits the activity of the APC in vitro, and we will use this compound to study APC regulation in cells. One of the mitotic inhibitors discovered in our Xenopus cell cycle screen paradoxically increases the rate at which cells exit mitosis in the presence of taxol. We will use this inhibitor to study the mechanism by which cells undergo this adaptation process. Understanding how exit from mitosis and adaptation is regulated will provide important insights for understanding how cancer cells respond to taxol treatment.

描述（由申请人提供）：我们的研究计划的目标是 了解脊椎动物细胞中有丝分裂的退出是如何调节的， 这一过程在癌细胞中被破坏。通过真核细胞的进展 周期是由精心定时的蛋白磷酸化和蛋白质 降解后期和有丝分裂的退出依赖于泛素依赖的 调节因子如securin和有丝分裂细胞周期蛋白的降解。这些蛋白质 被称为泛素连接酶的多亚基泛素化靶向 后期促进复合物（APC）。我们的目标是研究APC是如何 在脊椎动物细胞中通过寻找影响调节的化学物质 或者说这个复合体的活动。我们已经鉴定出几种化合物， 稳定非洲爪蟾卵提取物中细胞周期蛋白B并通过 一种新的机制。我们的目标是确定这些蛋白质的靶点， 使用生物化学表征和 基于亲和力的技术。我们还发现了一种化合物， 在体外抑制APC的活性，我们将使用这种化合物来 研究APC在细胞中的调节。在我们的研究中发现的一种有丝分裂抑制剂 非洲爪蟾细胞周期筛选矛盾地增加了细胞退出的速率 在紫杉醇存在下的有丝分裂。我们将使用这种抑制剂来研究 细胞进行这种适应过程的机制。了解如何 退出有丝分裂和适应的调节将提供重要的见解 了解癌细胞对紫杉醇治疗的反应。