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 生物起源以及这一过程中的错误如何导致人类疾病。中心粒是细胞的结构核心， 中心体是使微管成核以构建有丝分裂/减数分裂纺锤体和纤毛的细胞器。在正常 在细胞周期中，中心粒复制一次，以确保其拷贝数精确维持。的存在 多余中心粒是人类肿瘤的一个共同特征，并可促进染色体分离 这些错误足以驱动小鼠的肿瘤发展。为了保持基因组的完整性，细胞进化了 保护性中心粒监视途径，以限制具有额外中心粒的细胞的增殖。的目标 我们的应用是解开负责“感应”多余中心粒的分子机制， 评估该途径的失活是否促进具有额外中心粒的细胞中的肿瘤发展。 中心粒扩增触发PIDDosome的激活，PIDDosome是一种三聚体蛋白复合物， Caspase-2的激活平台。一旦激活，Caspase-2促进MDM 2的切割， P53的稳定性。然而，我们对额外中心粒是如何形成的理解存在着差距， 以及如何将该信息传递给PIDDosome以触发P53激活。为了解决这个 知识的差距，我们开发了一种全基因组筛选方法，以确定所需的基因，以阻止 具有额外中心粒的非转化细胞的生长。我们的初步数据显示， 在成熟中心粒上形成的PIDDosome负责激活中心粒扩增后的PIDDosome。在 本提案的目标1，我们将使用细胞生物学，遗传学和生物化学方法， 剖析细胞如何“感知”多余的中心粒以触发PIDDosome激活。在目标2中，我们 确定特异性灭活中心粒监视途径对增殖的影响， 在体内具有额外中心粒的细胞的致癌转化。我们非常适合从事这些研究， 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 体内中心粒扩增;以及我们与Regot和Loncarek实验室的合作关系， 是高分辨率活细胞成像和中心粒相关光/EM分析的世界专家 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额外的中心粒而稳健地增殖提供帮助。

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.