Regulation of Messenger RNA Turnover in Mammalian Cells

哺乳动物细胞中信使 RNA 周转的调节

• 批准号: 9895834
• 负责人: Ann-Bin Shyu
• 金额: $ 45.75万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9895834
• 关键词: 3' Untranslated Regions; Allergic inflammation; Area; Autoimmune Diseases; Biology; Complex; Cytoplasm; Development; Event; Excision; Gene Expression; Individual; Kinetics; Laboratories; Link; Longevity; Malignant Neoplasms; Mammalian Cell; Messenger RNA; Metabolic; Modification; Pathologic; Pathway interactions; Phase; Phosphorylation; Play; Poly(A) Tail; Polyadenylation; Process; Protein Biosynthesis; Protein Isoforms; Proteins; RNA; RNA Degradation; Regulation; Research; Role; Shapes; Signal Transduction; Stimulus; Therapeutic Agents; human disease; mRNA Decay; mRNA Stability; novel therapeutics; protein complex; transcriptome

Project Description Research in my laboratory focuses on elucidating the principles and regulatory mechanisms that govern messenger RNA turnover in mammalian cells. mRNA turnover plays an essential role in regulating gene expression via control of mRNA stability and quality, both globally and at the level of individual mRNAs. In mammalian cells, all major modes of mRNA decay are triggered by deadenylation (i.e., the removal of the poly(A) tails from the 3' end of mRNAs), a rate-limiting process involving two consecutive kinetic phases. Although previous studies provided a clear picture of the mechanistic steps and participating factors of mRNA decay pathways, relatively little is known about the impact of deadenylation and its modulation on mRNA turnover at the transcriptome level. Particularly lacking is an understanding of how coordinated changes in stability for whole groups of mRNAs contribute to programming or reprogramming of the transcriptome when mammalian cells respond to intra- or extra-cellular stimuli. In the cytoplasm, mRNAs fulfill their functions in the form of mRNA-protein complexes (mRNPs). mRNPs are highly dynamic entities, being continuously remodeled by rapid exchanges of their protein constituents, dictating individual mRNAs' fates at each step of their lifespan. Any inappropriate remodeling of an mRNP complex has the potential to disrupt its proper engagement in downstream events. Currently, one exciting and underexplored area of research in RNA biology is the remodeling of mRNPs at individual, group, and global levels during the process of mRNA deadenylation and decay. Our present proposal focuses on three seemingly disparate aspects of mammalian RNA biology that are linked by their potential to shape the mammalian transcriptome through modulating global mRNA turnover and mRNP remodeling. These are: 1) Alternative 3' end processing and polyadenylation (APA), which generates mRNA isoforms with distinct 3' untranslated regions; 2) mRNA N6-methyladenosine (m6A) modification, which creates mRNA isoforms with different metabolic fate; and 3) Phosphorylation of ancillary deadenylation factors, which alters mRNA deadenylation and decay. In the past few years, we have made several key findings regarding these three areas that have helped lay the groundwork for the proposed studies in this application. We have also adapted and further developed key analytical approaches to elucidating the impacts of the targeted processes on mRNA turnover across the transcriptome and the mechanisms by which deadenylation impacts mRNA stability through mRNP remodeling. Successful completion of the proposed studies will offer a new framework for elucidating the signal-dependent regulation of mRNA stability and mRNP remodeling at the transcriptome level, and the results will significantly expand understanding of the fundamental principles governing eukaryotic mRNA turnover.

项目描述 我实验室的研究重点是阐明其原理和调节机制 控制哺乳动物细胞中信使 RNA 的周转。 mRNA 周转在调节中起着重要作用 通过控制 mRNA 的稳定性和质量来实现基因表达，无论是在全球水平还是在个体水平 mRNA。在哺乳动物细胞中，mRNA 衰变的所有主要模式都是由去腺苷酸化触发的（即， 从 mRNA 的 3' 端去除 Poly(A) 尾），这是一个涉及两个连续的限速过程 动力学阶段。尽管之前的研究提供了清晰的机制步骤和 mRNA 衰变途径的参与因素，对于脱腺苷酸化的影响知之甚少 及其在转录组水平上对 mRNA 更新的调节。尤其缺乏的是对 整组 mRNA 稳定性的协调变化如何有助于编程或 当哺乳动物细胞对细胞内或细胞外刺激做出反应时，转录组会重新编程。在 在细胞质中，mRNA 以 mRNA-蛋白质复合物 (mRNP) 的形式发挥其功能。 mRNP 是 高度动态的实体，通过其蛋白质成分的快速交换而不断重塑， 决定个体 mRNA 在其生命周期每一步的命运。 mRNP 的任何不当重塑 复杂的系统有可能破坏其对下游事件的正常参与。目前，一项激动人心的 RNA 生物学中尚未开发的研究领域是个体、群体和个体的 mRNP 重塑。 mRNA 去腺苷酸化和衰变过程中的整体水平。 我们目前的提案重点关注哺乳动物 RNA 生物学的三个看似不同的方面 通过调节整体 mRNA 来塑造哺乳动物转录组的潜力相关联 营业额和 mRNP 重塑。它们是：1) 替代 3' 末端加工和聚腺苷酸化 (APA)， 产生具有独特 3' 非翻译区的 mRNA 同工型； 2) mRNA N6-甲基腺苷 (m6A) 修饰，产生具有不同代谢命运的 mRNA 亚型；和 3) 磷酸化 辅助去腺苷化因子，改变 mRNA 去腺苷化和衰变。在过去的几年里，我们 就这三个领域取得了几项重要发现，这些发现有助于为 本申请中提出的研究。我们还调整并进一步开发了关键的分析 阐明目标过程对 mRNA 周转率影响的方法 转录组和去腺苷酸化通过 mRNP 影响 mRNA 稳定性的机制 重塑。拟议研究的成功完成将为阐明 转录组水平上 mRNA 稳定性和 mRNA 重塑的信号依赖性调节，以及 结果将显着加深对真核 mRNA 控制基本原理的理解 周转。