Chemical Genetic Studies of Mitosis

有丝分裂的化学遗传学研究

• 批准号: 6623408
• 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/6623408
• 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）：我们研究计划的目标是 了解脊椎动物细胞中如何调节有丝分裂的退出以及这是如何进行的 癌细胞中的过程被破坏。真核细胞的进展 周期由仔细定时的蛋白质磷酸化和蛋白质控制 降解。后期和有丝分裂退出取决于泛素依赖性 调节因子如 securin 和有丝分裂周期蛋白的降解。这些蛋白质 被称为泛素连接酶的多亚基泛素连接酶靶向泛素化 后期促进复合体或环体 (APC)。我们的目标是研究 APC 是如何 通过寻找影响调节的化学物质来控制脊椎动物细胞 或该复合体的活动。我们已经鉴定出几种化合物 稳定非洲爪蟾卵提取物中的细胞周期蛋白 B，并通过阻断有丝分裂的退出 一种新颖的机制。我们的目标是确定这些蛋白质的靶标 结合使用生化表征和 基于亲和力的技术。我们还发现了一种化合物，可以直接 在体外抑制APC的活性，我们将使用该化合物来 研究细胞中 APC 的调节。我们发现的有丝分裂抑制剂之一 非洲爪蟾细胞周期筛选反而增加了细胞退出的速率 有丝分裂在紫杉醇存在下。我们将使用该抑制剂来研究 细胞经历这种适应过程的机制。了解如何 有丝分裂的退出和适应受到调节将提供重要的见解 了解癌细胞如何响应紫杉醇治疗。