Biochemical, proteomic and microscopic insights into regulation of nucleolar structure and function

对核仁结构和功能调节的生物化学、蛋白质组学和微观见解

• 批准号: RGPIN-2015-06674
• 负责人: TrinkleMulcahy, Laura
• 金额: $ 2.48万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=685178
• 关键词: Biochemical; proteomic; microscopic; insights; into

The mammalian nucleolus is a non membrane-bound nuclear organelle that forms around tandem repeats of ribosomal DNA and is best known for its essential role in the coordination of ribosome biogenesis, which supplies the cell with the ribosome complexes required for protein synthesis. This structure is dynamic, disassembling and reassembling throughout each cell cycle in mammalian cells and reorganizing its internal structure in response to various cellular stresses. ***Recent biochemical and proteomic analyses have revealed a much wider nucleolar functional complexity than was previously appreciated, linking this organelle to roles in cell cycle regulation, DNA damage repair, telomere metabolism, RNA processing and coordination of the cellular response to various stresses. Given that nucleolar dysfunction has been linked to several disease states, including cancer, accelerated aging and viral infection, it is clear that precise coordination of these diverse individual pathways is essential for its proper function.***    Despite major advances in recent years, including a more detailed catalogue of nucleolar protein, DNA and RNA components, important questions remain to be answered with regard to which specific factors provide the nucleolus with its structural integrity and how its dynamic organization is regulated. Much also remains to be learned about the full range of biological processes that occur within, or involve, the nucleolus, and the relationship between sub-nucleolar structure and specific functions at the molecular level.***    Our interest lies primarily in the structure/function relationship of non-canonical nucleolar components (i.e. those not involved directly in ribosome biogenesis), and we hypothesize that their functions fit within a defined architecture, similar to the structure/function relationship observed for components involved in ribosome biogenesis pathways. The main objectives of this project are thus to characterize nucleolar proteins that mediate non-ribosomal functions and define the regulatory mechanisms that underlie this organelle's coordinated organization, and we propose to apply a combination of powerful new super-resolution imaging and quantitative proteomic technologies to carry them out. ***    Understanding the regulation of nucleolar assembly/maintenance and function remains a fundamental question in cell biology. Given that a detailed description of the protein content of the nucleolus has emerged over the past few years and yet we still do not know how their diverse functions are regulated (and in some cases, what their functions actually are) this structure clearly remains a source of significant new discoveries and undoubtedly some more surprises for the foreseeable future. ***    **

哺乳动物核仁是一种围绕核糖体DNA串联重复序列形成的非膜结合核细胞器，以其在核糖体生物发生协调中的重要作用而闻名，核糖体生物发生为细胞提供蛋白质合成所需的核糖体复合体。这种结构是动态的，在哺乳动物细胞的每个细胞周期中进行分解和重组，并在不同的细胞压力下重组其内部结构。*最近的生化和蛋白质组学分析揭示了核仁功能的复杂性，这与细胞周期调节、DNA损伤修复、端粒新陈代谢、RNA处理和协调细胞对各种胁迫的反应有关。鉴于核仁功能障碍与几种疾病状态有关，包括癌症、加速衰老和病毒感染，很明显，这些不同的个体途径的精确协调对于其正常功能至关重要。*尽管近年来取得了重大进展，包括更详细的核仁蛋白质、DNA和RNA成分目录，但关于哪些特定因素提供核仁结构完整性以及如何调节其动态组织，仍有重要问题有待回答。对于发生在核仁内或涉及核仁的所有生物学过程，以及亚核仁结构和分子水平上特定功能之间的关系，我们还有很多需要了解的。*我们的兴趣主要在于非规范核仁成分(即那些不直接参与核糖体生物发生的核仁成分)的结构/功能关系，我们假设它们的功能符合定义的体系结构，类似于观察到的核糖体生物发生途径中涉及的成分的结构/功能关系。因此，该项目的主要目标是确定介导非核糖体功能的核仁蛋白的特征，并确定该细胞器协调组织的调节机制，我们建议应用强大的新的超分辨率成像和定量蛋白质组学技术的组合来实现这些功能。*了解核仁组装/维持和功能的调节仍然是细胞生物学中的一个基本问题。鉴于过去几年出现了对核仁蛋白质含量的详细描述，但我们仍然不知道它们的不同功能是如何调节的(在某些情况下，它们的实际功能是什么)，这种结构显然仍然是重大新发现的来源，无疑在可预见的未来会有更多惊喜。*中国政府**