Nonsense-mediated mRNA decay and beyond

无义介导的 mRNA 衰减及其他

基本信息

批准号：
10622727
负责人：
Lynne E Maquat
金额：
$ 64.13万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-01 至 2028-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10622727
关键词：
Affect Bacterial Infections Binding Biological Process Biology COVID-19 Cardiomyopathies Categories Cell Nucleus Cell physiology Cells Complex Cytoplasm Development Disease Environment Etiology Exons Fragile X Syndrome Frameshift Mutation Gene Expression Genes Genetic Genetic Transcription Goals Health Hereditary Disease Human Immune response In Vitro Inherited Innate Immune Response Intellectual functioning disability Mammalian Cell Mediating Messenger RNA Metabolism Mitochondria Molecular Mus Muscle Fibers Neuromuscular Diseases Nonsense Codon Nonsense Mutation Nuclear Outcome Pathogenesis Pharmacotherapy Production Proteins RNA Cap-Binding Proteins RNA Polymerase III RNA Splicing RNA metabolism RNA-Binding Proteins Research Research Personnel Role Runaway Time Transcription Coactivator Gene Translations Virus Diseases Work autism spectrum disorder boys cytokine release syndrome fascinate girls human disease insight interest mRNA Decay mRNA Precursor mRNA Translation prevent protein function sarcopenia therapeutically effective

项目摘要

This MIRA application extends our decades-long research on nonsense-mediated mRNA decay (NMD) and how NMD factors can function in other aspects of cellular metabolism. NMD is a fundamental biological process by which mammalian cells eliminate mRNAs containing a nonsense codon deriving from a genetic or acquired frameshift or nonsense mutation. NMD also eliminates an estimated one-third of mRNAs that cells produce by routine mistakes made during gene transcription and/or mRNA production. Over the years, we have worked to elucidate the molecular mechanism of NMD. As one of many outcomes, we have established a “rule” that clinicians and researchers use to predict which nonsense codons result in recessively inherited vs. dominantly inherited disease. We have also demonstrated how cells regulate the efficiency of NMD as an adaptive mechanism during changing environments, e.g. during development, differentiation, or drug treatments. This application pursues our serendipitous finding that NMD is hyperactivated in fragile X syndrome (FXS), which is the most common single-gene cause of intellectual disability and autism, affecting 1/4000 boys and 1/6000-8000 girls. We aim to understand how the protein that is missing in FXS functions via interactions with other proteins and mRNAs to protect these mRNAs from translation and decay. We also aim to decipher the mechanism by which the RNA-binding protein Staufen prevents a runaway immune response. On another front, our long-time interest in mechanistic connections that span pre-mRNA splicing in the nucleus to mRNA translation and decay in the cytoplasm will be extended to include gene transcription and nuclear mRNA decay. We have long been fascinated by the structural dynamics and functions of the largely nuclear cap-binding heterodimer CBP80−CBP20, which binds co-transcriptionally to the 5'-cap of nascent pre-mRNAs. While our past interests have focused on the role of CBP80−CBP20 in the pioneer round(s) of cytoplasmic translation, during which we have shown exon-junction complex-mediated NMD occurs, we aim to understand roles of CBP80−CBP20 in the nucleus. As one example, we are studying the mechanism by which a master transcriptional co-activator of genes whose products regulate critical cellular processes engages with CBP80−CBP20 so as to promote the expression of an understudied category of RNA polymerase III- transcribed genes. In related work, we are studying connections between CBP80−CBP20 and the little- understood, and so-called, nuclear cap-binding protein (NCBP)3. We aim to elucidate the significance of our finding that NCBP3 regulates newly made mRNAs from genes encoding proteins that function in mitochondrial biology. These connections will be examined in skeletal-muscle cells in vitro and ex vivo, the latter using mice, which should lend insight into the etiology and pathogenesis of many human diseases that include sarcopenia, neuromuscular disorders, and cardiomyopathies. While our interests are broad, they are connected by the goal to understand molecular mechanisms in health and in disease, with a focus on RNA metabolism.

该 MIRA 应用扩展了我们数十年来对无义介导的 mRNA 衰减 (NMD) 的研究， NMD 因子如何在细胞代谢的其他方面发挥作用是一个基本的生物学问题。哺乳动物细胞消除含有源自遗传或基因的无义密码子的 mRNA 的过程。获得性移码或无义突变也会消除细胞中大约三分之一的 mRNA。多年来，我们通过在基因转录和/或 mRNA 生产过程中犯下的常规错误来生产。我们致力于阐明 NMD 的分子机制，作为众多成果之一，我们建立了一个新手和研究人员用“规则”来预测哪些无义密码子会导致隐性遗传，哪些会导致隐性遗传。我们还主要证明了细胞如何调节 NMD 作为一种环境变化期间的适应机制，例如发育、分化或药物期间该应用程序追求我们偶然发现的 NMD 在脆性 X 细胞中过度激活。综合症（FXS），这是智力障碍和自闭症最常见的单基因原因，影响 1/4000 的男孩和 1/6000-8000 的女孩我们的目标是了解 FXS 中缺失的蛋白质如何发挥作用。我们还致力于与其他蛋白质和 mRNA 相互作用，以保护这些 mRNA 免于翻译和衰变。破译 RNA 结合蛋白 Staufen 防止失控免疫反应的机制。另一方面，我们长期以来对细胞核中 mRNA 前体剪接的机械连接感兴趣 mRNA翻译和细胞质中的衰变将扩展到包括基因转录和细胞核长期以来，我们对主要核的结构动力学和功能着迷。帽结合异二聚体 CBP80−CBP20，与新生前 mRNA 的 5'-帽共转录结合。虽然我们过去的兴趣集中在 CBP80−CBP20 在细胞质的先锋轮中的作用翻译，在此期间我们已经表明外显子连接复合物介导的 NMD 发生，我们的目的是了解作为一个例子，我们正在研究 CBP80−CBP20 在细胞核中的作用。其产物调节关键细胞过程的基因转录共激活因子与 CBP80−CBP20 以促进正在研究的 RNA 聚合酶 III- 类别的表达在相关工作中，我们正在研究 CBP80−CBP20 和小基因之间的联系。我们的目标是阐明我们的理解，即所谓的核帽结合蛋白（NCBP）3的重要性。发现 NCBP3 调节来自编码在线粒体中发挥作用的蛋白质的基因的新产生的 mRNA 生物学。这些连接将在体外和离体骨骼肌细胞中进行检查，后者使用小鼠，这应该有助于深入了解许多人类疾病的病因和发病机制，包括肌肉减少症，虽然我们的兴趣广泛，但它们通过目标联系在一起。了解健康和疾病的分子机制，重点是 RNA 代谢。