Supernumerary Centrosomes and Cell Proliferation

多余中心体和细胞增殖

• 批准号: 10573215
• 负责人: David M Glover
• 金额: $ 48.35万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10573215
• 关键词: Actins; Affect; Apoptosis; Brain; Cell Cycle; Cell Cycle Arrest; Cell Cycle Regulation; Cell Death; Cell Proliferation; Cell Proliferation Regulation; Cell surface; Cells; Centrioles; Centrosome; Cerebral cortex; Cilia; Coupling; Cytokinesis; Cytoplasm; Cytoskeleton; Defect; Development; Developmental Process; Disease; Ensure; Excision; Functional disorder; GTPase-Activating Proteins; Generations; Genes; Guanine Nucleotide Exchange Factors; Human; Hyperplasia; Inherited; Knock-out; Lead; Length; Liquid substance; Malignant Neoplasms; Mediating; Microcephaly; Microtubule-Organizing Center; Microtubules; Mitosis; Mitotic spindle; Modeling; Mus; Organelles; PAK-1 kinase; PLK1 gene; Pathway interactions; Pharmaceutical Preparations; Phosphorylation; Physiological Processes; Pilot Projects; Predisposition; Procentriole; Prognosis; Proliferating; Protein Kinase; Proteins; Regulation; Research; Role; S phase; Signal Pathway; Signal Transduction; Signaling Protein; Site; System; TP53 gene; Testing; Tissues; base; cancer therapy; cell motility; ciliopathy; cilium biogenesis; cohesion; genome wide screen; kinetosome; knock-down; neoplastic cell; novel; overexpression; p53-binding protein 1; permissiveness; protein complex; receptor; response; stem cell proliferation; translational applications; tumor; tumorigenesis; ubiquitin isopeptidase

PROJECT SUMMARY The centriole is a conserved organelle of metazoans that is found at the core of microtubule organizing centers, centrosomes, and at the base of cilia and flagellae. Centriole dysfunction leads to a wide range of diseases including the developmental defects of ciliopathies; defective brain development in microcephaly; and in cancer where supernumerary or defective centrosomes are associated with poor prognosis. Centriole duplication is promoted by Plk4, which phosphorylates cartwheel proteins to mediate their assembly. We and others have found that induction of Plk4-mediated centriole amplification results in hyperplasia of several tissues and increases the susceptibility to tumorigenesis in the mouse in the absence of the p53 tumor suppressor. Both the loss and acquisition of extra centrosomes normally block cell proliferation. However, the pathway that responds to loss of centrosomes differs from several pathways that respond to supernumerary centrosomes. Therefore, to identify proteins that signal or respond to the presence of extra centrosomes, we carried out a genome-wide screen for genes that when deleted or knocked- down permit the proliferation of cells that have elevated levels of Plk4. This has identified new pathways whereby cells respond to supernumerary centrosomes: a previously unknown involvement of specific Rac-mediated signaling that regulates centriole duplication; proteins that regulate the elongation, disengagement and separation of centrioles; and negative regulators of ciliogenesis. Here we follow three approaches to understand how centriole number is regulated in proliferating cells. First, we will determine how the Arh15gap GTPase Activating Protein acts upon the Pak1/2 protein kinases to regulate Plk4 levels or activity and upon Arp2/3 to regulate spindle associated actin to permit an increase in centriole- and cell-cycle arrest. Second, we examine how known components of the centriole affect the execution of the centriole and cell cycles at unexpected points. We will determine how the Usp33 deubiquitinase regulates the centriole capping protein complex to protect the nascent procentriole and how proteins required in the centriole cycle for both centriole disengagement and centrosome separation contribute to the block to cell proliferation in the presence of supernumerary centrosomes. Finally, we will explore how negative regulators of ciliogenesis block primary cilium formation in the presence of extra centrioles in such a way as to arrest cell proliferation. We anticipate that this research will advance our understanding of the multiple ways in which cells respond to supernumerary centrosomes. It will identify pathways that can be targeted for restoring centriole numbers or cell cycle regulation in tumor cells or for targeting such cells for apoptosis. This will find translational application in developing multiple drug strategies for cancer treatment.

项目概要 中心粒是后生动物的保守细胞器，位于微管的核心 组织中心、中心体以及纤毛和鞭毛的基部。中心粒功能障碍导致 多种疾病，包括纤毛病的发育缺陷；大脑发育缺陷 小头畸形；在癌症中，多余或有缺陷的中心体与 预后不良。中心粒复制由 Plk4 促进，Plk4 磷酸化车轮蛋白 调解他们的集会。我们和其他人发现 Plk4 介导的中心粒的诱导 扩增导致多种组织增生并增加肿瘤发生的易感性 在缺乏 p53 肿瘤抑制因子的小鼠中。 额外中心体的丢失和获得通常都会阻碍细胞增殖。然而， 响应中心体丢失的途径不同于响应中心体丢失的几种途径 多余的中心体。因此，为了鉴定发出信号或响应存在的蛋白质 除了中心体之外，我们对基因进行了全基因组筛选，当删除或敲除这些基因时- 下调允许 Plk4 水平升高的细胞增殖。这已经确定了新的 细胞对多余中心体作出反应的途径：以前未知的参与 调节中心粒复制的特定 Rac 介导的信号传导；调节蛋白质 中心粒的伸长、脱离和分离；和纤毛发生的负调节因子。 在这里，我们按照三种方法来了解中心粒数量在增殖过程中是如何调节的 细胞。首先，我们将确定 Arh15gap GTP 酶激活蛋白如何作用于 Pak1/2 蛋白激酶调节 Plk4 水平或活性，并通过 Arp2/3 调节纺锤体相关肌动蛋白 以增加中心粒和细胞周期停滞。其次，我们检查已知的组件 中心粒的变化会在意想不到的时刻影响中心粒和细胞周期的执行。我们将 确定 Usp33 去泛素酶如何调节中心粒加帽蛋白复合物以保护 新生原中心粒以及中心粒循环中蛋白质如何实现中心粒脱离 和中心体分离有助于在存在多余物质的情况下阻止细胞增殖 中心体。最后，我们将探讨纤毛发生的负调节因子如何阻止初级纤毛 在存在额外中心粒的情况下形成，从而阻止细胞增殖。 我们预计这项研究将增进我们对细胞发挥作用的多种方式的理解。 对多余中心体做出反应。它将确定可用于恢复的目标途径 肿瘤细胞中的中心粒数量或细胞周期调节或用于靶向此类细胞进行凋亡。这 将在开发癌症治疗的多种药物策略中找到转化应用。