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.

项目总结 中心粒是一种保守的后生动物细胞器，位于微管的核心。 组织中心，中心体，纤毛和鞭毛的底部。中心粒功能障碍导致 广泛的疾病，包括纤毛疾病的发育缺陷；大脑发育缺陷 在小头畸形症中；在癌症中，多出或有缺陷的中心体与 预后不良。中心粒复制是由Plk4促进的，Plk4使车轮蛋白磷酸化以 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 扩增会导致几种组织的增殖，并增加肿瘤发生的易感性 在小鼠体内没有抑癌基因P53。 额外中心体的丢失和获得通常都会阻止细胞的增殖。然而， 对中心体丢失作出反应的途径不同于对中心体丧失作出反应的几种途径 额外的中心体。因此，为了识别发出信号或响应存在的蛋白质 额外的中心体，我们进行了全基因组的基因筛查，当缺失或敲除时- 低水平允许Plk4水平升高的细胞增殖。这已经确定了新的 细胞对多余的中心体作出反应的途径：一个以前未知的参与 调节中心粒复制的特定RAC介导的信号；调节 中心粒的伸长、脱离和分离；纤毛发生的负调控。 在这里，我们遵循三种方法来理解中心粒数在增殖过程中是如何被调节的。 细胞。首先，我们将确定Arh15Gap GTP酶激活蛋白如何作用于pak1/2 调节Plk4水平或活性的蛋白激酶和调节纺锤体相关肌动蛋白的Arp2/3 以允许中心粒和细胞周期停滞的增加。第二，我们检查已知组件是如何 中心粒在意想不到的点上影响中心粒和细胞周期的执行。我们会 确定Usp33脱泛素酶如何调节中心粒封顶蛋白复合体以保护 新生的前着丝粒以及中心粒周期中两个中心粒分离所需的蛋白质 而中心体的分离有助于在多余细胞存在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性调节因子如何阻断原发纤毛。 以阻止细胞增殖的方式在存在额外中心粒的情况下形成。 我们预计，这项研究将促进我们对细胞以多种方式 对多余的中心体作出反应。它将确定可作为恢复目标的路径 肿瘤细胞中的中心粒数量或细胞周期调节，或用于靶向肿瘤细胞的凋亡。这 将在开发癌症治疗的多种药物策略方面找到翻译应用。