Molecular mechanism that suppresses the proliferation of cells with supernumerary centrioles

项目摘要 我们研究的长期目标是了解控制中心粒的分子机制。 生物发生以及这一过程中的错误如何导致人类疾病。中心粒是结构的核心 中心体，核化微管以形成有丝分裂/减数分裂纺锤体和纤毛的细胞器。在正常情况下 细胞周期，中心粒复制一次，以确保其拷贝数被精确地保持。.的存在 多余的中心粒是人类肿瘤的共同特征，可以促进染色体分离 足以推动小鼠肿瘤发展的错误。为了保持基因组的完整性，细胞进化了 保护中心粒监视途径，以限制具有额外中心粒的细胞的增殖。的目标是 我们的应用是解开负责‘感知’额外中心粒的分子机制，并 评估这一途径的失活是否促进了具有额外中心粒的细胞中的肿瘤发展。 中心粒放大触发PIDDosome的激活，PIDDosome是一种三聚体蛋白质复合体，起着 Caspase-2的激活平台。一旦激活，Caspase-2促进MDM2和 随后P53的稳定。然而，我们对额外中心粒的理解存在差距。 以及该信息如何传递到PIDDosome以触发P53激活。要解决这个问题 知识缺口，我们开发了一种全基因组筛选方法来识别阻止病毒感染所需的基因 有额外中心粒的未转化细胞的生长。我们的初步数据显示，远端附件 成熟中心粒上的形式负责在中心粒扩增后激活PIDDosome。在……里面 这项提案的目标1我们将使用细胞生物学、遗传学和生化方法来机械地 剖析细胞如何“感觉”多余的中心粒来触发PIDDosome激活。在目标2中，我们将 确定特异性失活中心粒监视通路对细胞增殖和 具有额外中心粒的细胞在体内的致癌转化。我们非常适合从事这些研究，因为 我们在研究中心粒生物学方面的专业知识；我们开发了一种独特的小鼠模型来研究 体内中心粒放大；以及我们与里戈特和朗凯克实验室的合作关系，世界卫生组织 是高分辨率活细胞成像和中心粒相关光/EM分析方面的世界专家 超微结构。了解正常细胞如何检测中心粒扩增解决了一个基本问题 这将为了解非整倍体肿瘤细胞如何适应通过额外的中心粒强劲地增殖提供了洞察力。

Project Summary The long-term goal of our research is to understand the molecular mechanisms that control centriole biogenesis and how errors in this process contribute to human disease. Centrioles are the structural core of centrosomes, organelles that nucleate microtubules to build mitotic/meiotic spindles and cilia. During a normal cell cycle, centrioles duplicate once to ensure their copy number is precisely maintained. The presence of supernumerary centrioles is a common feature of human tumors and can promote chromosome segregation errors that are sufficient to drive tumor development in mice. To maintain genome integrity, cells have evolved a protective centriole surveillance pathway to restrict the proliferation of cells with extra centrioles. The goal of our application is to unravel the molecular mechanism responsible for ‘sensing’ supernumerary centrioles and evaluate whether inactivation of this pathway facilitates tumor development in cells with extra centrioles. Centriole amplification triggers the activation of the PIDDosome, a trimeric protein complex that acts as an activation platform for Caspase-2. Once activated, Caspase-2 promotes the cleavage of MDM2 and subsequent stabilization of P53. However, there exists a gap in our understanding of how extra centrioles are sensed and how this information is relayed to the PIDDosome to trigger P53 activation. To address this knowledge gap, we developed a genome-wide screening approach to identify genes required to arrest the growth of non-transformed cells with extra centrioles. Our preliminary data show that distal appendages that form on mature centrioles are responsible for activating the PIDDosome following centriole amplification. In Aim 1 of this proposal we will use cell biological, genetic and biochemical approaches to mechanistically dissect how cells ‘sense’ supernumerary centrioles to trigger PIDDosome activation. In Aim 2, we will determine the impact of specifically inactivating the centriole surveillance pathway on the proliferation and oncogenic transformation of cells with extra centrioles in vivo. We are well suited to pursue these studies given our expertise in studying centriole biology; our development of a unique mouse model to study the impact of centriole amplification in vivo; and our collaborative relationship with the Regot and Loncarek laboratories, who are world-experts in high resolution live-cell imaging and correlative light/EM analysis of centriole ultrastructure. Understanding how normal cells detect centriole amplification addresses a fundamental question that will provide insight into how aneuploid tumor cells adapt to proliferate robustly with extra centrioles.