Eukaryotic RNA NAD capping and deNADding

真核 RNA NAD 加帽和 deNADding

• 批准号: 10622526
• 负责人: MEGERDITCH KILEDJIAN
• 金额: $ 36.51万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-02-27 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10622526
• 关键词: Aging; Amino Acids; Area; Bacteria; Biological; Biological Models; Biological Process; Biology; COVID-19; Cell Nucleus; Cell physiology; Cells; Cellular Stress; Complex; Cytoplasm; DNA; Data; Disease; Elements; Enzymes; Eukaryota; Eukaryotic Cell; Excision; Gene Expression; Genetic Transcription; Growth; Homeostasis; Human; In Vitro; Link; Mammalian Cell; Messenger RNA; Metabolic stress; Metabolism; Mitochondria; Mitochondrial Proteins; Mitochondrial RNA; Molecular; Nicotinamide adenine dinucleotide; Nuclear; Nuclear Decay; Nuclear RNA; Nutrient; Organism; Pathway interactions; Physiological; Play; Post-Transcriptional Regulation; Process; Publishing; RNA; RNA Caps; RNA Decay; RNA Polymerase II; RNA metabolism; RNA vaccine; Regulation; Research; Respiration; Role; Saccharomyces cerevisiae; Saccharomycetales; Starvation; Stress; Testing; Therapeutic; Transcript; Virus; Work; Yeasts; decapping enzyme; defined contribution; epitranscriptomics; genetic information; insight; mitochondrial dysfunction; novel; novel strategies; nuclease; poly A specific exoribonuclease; response; senescence; sugar; transmission process

RNA 5′ end capping provides a layer of “epitranscriptomic” regulation, influencing numerous aspects of RNA fate, including stability, processing, localization and translatability. Furthermore, enzymes that remove RNA 5′ end caps play critical roles in modulating these processes. Recently, a previously unknown form of RNA 5'-end capping has been identified in bacterial, yeast, and human cells. In this new form of RNA capping, the metabolite nicotinamide adenine dinucleotide (NAD) is added at the RNA 5′ end. In contrast to 7- methylguanylate (m7G) caps, which are added to mRNAs by a complex that associates with eukaryotic RNA polymerase II (RNAP II), NAD caps are primarily added by RNAP itself in bacteria and eukaryotic nuclear and mitochondrial transcripts. Thus, unlike m7G capping, which is observed in eukaryotes and certain eukaryotic viruses, NAD capping is likely to occur in most, if not all, organisms. Our recently published work along with our unpublished preliminary data, indicates that NAD capping targets mammalian RNAs for rapid decay. In addition, we have shown eukaryotic cells possess several enzymes capable of removing NAD caps and, furthermore, that the cellular functions of these “deNADding” enzymes are most evident during metabolic stress. An overall theme emerging from our data is that addition and removal of NAD caps play critical roles in mitochondrial function where NAD-capped mitochondrial-encoded transcripts and nuclear transcripts encoding mitochondrial proteins are modulated by NAD caps. To decipher the interplay between cellular assimilation of NAD and RNA metabolism we will define the functional role(s) of NAD caps and deNADding enzymes in both budding yeast and mammalian cells. The first aim will investigate the hypothesis that NAD capping of mitochondrial RNA plays a key role in maintaining NAD homeostasis with the NAD cap serving as a reservoir to sequester and release free NAD for proper mitochondrial energetics. The second aim will investigate the impact of NAD capping on nuclear encoded RNA and, in particular, explores the hypothesis that NAD capping in budding yeast provides a mechanism for the targeted decay of RNAs in response to nutrient stress. The third aim will determine how the NAD capping and deNADding of mammalian nuclear mRNAs encoding mitochondrial proteins contributes to mitochondrial function upon cellular stress and whether perturbation of the deNADding of these mRNAs contributes to mitochondrial dysfunction associated with aging. The proposed studies will provide new insight in an emerging area of RNA biology, post- transcriptional regulation in cellular metabolism and, furthermore, may provide a mechanistic framework for developing new approaches to control gene expression in normal and disease states.

RNA5‘末端封端提供了一层“表位转录”调节，影响了RNA的许多方面 命运，包括稳定性、加工性、本土化和可译性。此外，去除RNA的酶 5‘端帽在调节这些过程中起着关键作用。最近，一种以前未知的RNA形式 已经在细菌、酵母和人类细胞中发现了5‘端封顶。在这种新的RNA封顶形式中， 代谢物烟酰胺腺嘌呤二核苷酸(NAD)加在RNA5‘端。相比之下，7- 甲基鸟粪酸(M7G)帽，由与真核RNA结合的复合体添加到mRNA上 聚合酶II(RNAP II)，NAD帽主要由RNAP本身添加到细菌和真核细胞的核和 线粒体转录本。因此，与m7G封顶不同，m7G封顶在真核生物和某些真核生物中观察到 对于病毒，NAD封顶很可能发生在大多数(如果不是全部)生物体中。我们最近出版的作品以及 我们未发表的初步数据表明，NAD上限针对哺乳动物RNA的快速衰退。在……里面 此外，我们已经证明，真核细胞拥有几种能够去除NAD帽的酶， 此外，这些脱氧核糖核酸酶的细胞功能在新陈代谢过程中最为明显 压力。从我们的数据中得出的一个总体主题是，增加和取消NAD上限发挥着关键作用 在线粒体功能中，NAD封顶的线粒体编码转录本和核转录本 编码线粒体蛋白是由NAD帽调控的。破译细胞与细胞之间的相互作用 NAD和核糖核酸代谢的同化我们将确定NAD帽和deNADding的功能作用(S) 发芽酵母和哺乳动物细胞中的酶。第一个目标将调查NAD的假设 线粒体RNA的封顶在维持NAD动态平衡方面起着关键作用，NAD帽起着 为适当的线粒体能量学隔离和释放游离NAD的蓄水池。第二个目标是 研究NAD封顶对核编码RNA的影响，特别是探索假设 萌芽酵母中的NAD封顶为RNA的靶向衰退提供了一种机制，以响应 营养压力。第三个目标将决定哺乳动物核的NAD封顶和去NAD 编码线粒体蛋白的mRNAs有助于线粒体在细胞应激和 这些mRNAs脱氧核糖核酸脱氧核糖核酸的干扰是否与线粒体功能障碍有关 随着年龄的增长。拟议的研究将为RNA生物学的一个新兴领域提供新的见解，后 在细胞新陈代谢中的转录调节，此外，可能提供了一种机制框架 开发新的方法来控制正常和疾病状态下的基因表达。