Levels and functions of non-canonical nucleosides in messenger RNA

信使 RNA 中非经典核苷的水平和功能

• 批准号: 277203618
• 负责人: Professor Dr. Thomas Carell
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/277203618?language=en
• 关键词: Levels; functions; non; canonical; nucleosides

The discovery of reversible modification chemistry acting on nucleotides was a breakthrough discovery and led in the course to a gold rush of publications in epigenetic research. In particular, RNA moved back into focus, when it was discovered that messenger RNA may be more chemically diverse than originally believed. Most prominent is the adenosine modification m6A in this respect. Once introduced into mRNA, it serves an ever growing number of functions by interacting with specific reader proteins. We recently published a proteomic study that reveled completely novel connections, influencing disease relevant pathways not only by attraction of reader proteins, but also by repelling them. In the course of the rush, many other nucleotide modifications were identified in mRNA and also DNA. For example, m1A was found in mRNA and the base m6A in the DNA of a number of higher organisms, like algae, insects, worms and even mammals. Some initial discoveries however, had to be refined. As such it was found that both m1A and m5C are far less abundant in mRNA than originally postulated. The demethylating dioxygenase FTO, which was initially described as targeting m6A was recently found to accept predominantly m6Am like it is found in the cap structure. In addition, we could demonstrate with highly sensitive mass spectrometry that m6dA may not be a native component of mammalian DNA as frequently postulated. We will continue our efforts to verify the occurrence of modified bases in mRNA. Detailed data from our group and recent publications revealed that m62A and ms2i6A are found exclusively in rRNA and mitochondrial RNA, respectively. Nevertheless, the presence of in part highly modified nucleosides in mRNA remains a prime target of research. Therefore we are planning to perform a deep survey of nucleoside modifications in mRNA. We propose to study particularly pseudouridine and the 5’ cap structure in more detail. We will reveal their protein-interactome and unravel the functional mechanisms mediated by these interactions. The results will help us to understand the interplay of chemical modification on mRNA and essential cellular processes like translation into proteins.

作用于核苷酸的可逆修饰化学的发现是一个突破性的发现，并导致了表观遗传学研究出版物的淘金热。特别是，当人们发现信使 RNA 的化学多样性可能比最初认为的更加多样化时，RNA 重新成为人们关注的焦点。在这方面最突出的是腺苷修饰 m6A。一旦被引入 mRNA，它就会通过与特定的读取蛋白相互作用来发挥越来越多的功能。我们最近发表了一项蛋白质组学研究，揭示了全新的联系，不仅通过吸引读者蛋白，还通过排斥它们来影响疾病相关途径。在这一热潮中，人们在 mRNA 和 DNA 中发现了许多其他核苷酸修饰。例如，在许多高等生物（如藻类、昆虫、蠕虫甚至哺乳动物）的 mRNA 中发现了 m1A，在 DNA 中发现了碱基 m6A。然而，一些最初的发现必须加以完善。因此，我们发现 m1A 和 m5C 的 mRNA 丰度远低于最初假设的水平。去甲基双加氧酶 FTO 最初被描述为靶向 m6A，最近发现它主要接受 m6Am，就像在帽结构中发现的那样。此外，我们可以通过高度灵敏的质谱分析证明，m6dA 可能并不像人们经常假设的那样是哺乳动物 DNA 的天然成分。我们将继续努力验证 mRNA 中是否存在修饰碱基。我们小组和最近出版物的详细数据表明，m62A 和 ms2i6A 分别仅存在于 rRNA 和线粒体 RNA 中。尽管如此，mRNA 中部分高度修饰的核苷的存在仍然是研究的主要目标。因此，我们计划对 mRNA 中的核苷修饰进行深入研究。我们建议更详细地研究假尿苷和 5' 帽结构。我们将揭示它们的蛋白质相互作用组并揭示这些相互作用介导的功能机制。这些结果将帮助我们了解化学修饰对 mRNA 和重要细胞过程（如翻译成蛋白质）的相互作用。