Mechanism and regulation of nuclear RNA export

核RNA输出的机制和调控

• 批准号: 10672440
• 负责人: Benjamen H.W. Montpetit
• 金额: $ 44.02万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10672440
• 关键词: Address; Architecture; Biology; Cytoplasm; DNA; Data; Disease; Eukaryota; Event; Gene Expression; Genetic Transcription; Goals; Homeostasis; Human; Induced Mutation; Knowledge; Link; Mediating; Meiosis; Messenger RNA; Methodology; Mission; Molecular; Mutation; National Institute of General Medical Sciences; Nuclear; Nuclear Export; Nuclear Pore Complex; Nuclear RNA; Pathway interactions; Poly A; Polyadenylation; Process; Proteins; RNA; RNA Decay; RNA Processing; RNA Splicing; RNA Transport; RNA-Binding Proteins; RNA-Protein Interaction; Regulation; Research; Role; Structure; TAF15 gene; Technology; Transcript; Transfer RNA; Translations; United States National Institutes of Health; Untranslated RNA; Virus; Virus Replication; mRNA Export; novel; programs; protein complex

ABSTRACT Nuclear mRNA export is a fundamental component of the gene expression program in eukaryotes and is intimately linked to upstream (transcription and nuclear RNA surveillance) and downstream (translation and cytoplasmic RNA decay) events. Within my group, we study the mechanisms by which the fate (nuclear export vs. decay) of an mRNA-protein complex (mRNP) is determined and regulated. Current studies within the lab focus on understanding how RNA-binding protein (RBP) constituents of an mRNP direct nuclear RNA processing and export, including interactions with the nuclear pore complex (NPC). Recent efforts in my group have led to the discovery of a novel function for the mRNA export factor Dbp5 in tRNA export and the SR-like protein Npl3 in the meiotic splicing regulatory network. In addition, we have characterized mutation-induced alterations in polyadenylation that promote imbalances in the distribution of RBPs between mRNA and non-coding (nc)RNA processes and the loss of nuclear RNA processing homeostasis. At the core of these events is the mRNP, which remains ill-defined in terms of how changes in mRNP architecture, including gain or loss of specific RBPs, directs distinct transcript fates, including mRNA export. Consequently, our goals over the next five years focus on a quantitative interrogation of mRNP biology, encompassing function, regulation, and structure. Pursuing this goal is timely given the newly amassed knowledge of RBPs central to both mRNA and ncRNA biology, the technologies available to apply these questions, and the need to understand how disease states arise in the context of mutations within conserved RBP components or their modulation by viruses. A critical factor in mRNA export is Dbp5 (DDX19 in humans), a highly conserved DEAD-box protein (DBP) that mediates directional mRNP export through NPCs via modulation of RNA-protein interactions. Dbp5 is activated by the NPC component Gle1- InsP6, which we have also shown to be required for tRNA export, in addition to the known role of Gle1 in mRNA export. Questions that must be addressed to close major knowledge gaps in the RNA export field include: (1) How is mRNP composition regulated to achieve directional transport through NPCs? (2) Are mRNA and ncRNA export pathways integrated or distinct? (3) Is there coordination of RNA processing and export via shared RBPs between mRNPs and ncRNPs? By addressing these questions, we expect to provide a molecular framework that describes how Dbp5 and other RBPs engage, modify, and direct nuclear RNA processing and export. These data are essential to understanding the flux of RNPs through NPCs to match cellular demand and how altering this process by mutation leads to disease. In addition, these results will contribute to the understanding and methodology within the DEAD-box protein, RNA transport, and gene expression fields, thereby fundamentally contributing to the study of RNA biology.

摘要 核mRNA输出是真核生物基因表达程序的基本组成部分， 与上游（转录和核RNA监视）和下游（翻译和 细胞质RNA衰变）事件。在我的小组中，我们研究了命运（核出口） vs. mRNA-蛋白质复合物（mRNP）的降解）被确定和调节。实验室内的当前研究 重点是了解mRNP的RNA结合蛋白（RBP）成分如何指导核RNA加工 和输出，包括与核孔复合物（NPC）的相互作用。我的团队最近的努力 mRNA输出因子Dbp 5在tRNA输出和SR样蛋白Np 13中的新功能的发现 在减数分裂剪接调控网络中。此外，我们已经描述了突变诱导的改变， 多聚腺苷酸化促进RBP在mRNA和非编码（nc）RNA之间的分布不平衡 过程和核RNA加工稳态的丧失。这些事件的核心是mRNP， 在mRNP架构的变化（包括特定RBP的增加或减少）如何指导 不同的转录物命运，包括mRNA输出。因此，我们在未来五年的目标集中在一个 mRNP生物学的定量询问，包括功能，调节和结构。追求这一目标 及时地考虑到新积累的对mRNA和ncRNA生物学至关重要的RBP知识， 可用于应用这些问题的技术，以及了解疾病状态如何在 保守的RBP组分内的突变或它们被病毒调节的背景。mRNA中的一个关键因素 出口是Dbp 5（人类中的DDX 19），一种高度保守的死亡盒蛋白（DBP），介导定向mRNP 通过调节RNA-蛋白质相互作用通过NPC输出。Dbp 5被NPC组分Gle 1激活。 InsP 6，除了已知的Gle 1在mRNA表达中的作用外，我们还发现它是tRNA输出所必需的。 导出.为了填补RNA出口领域的主要知识空白，必须解决的问题包括：（1） 如何调节mRNP组成以实现通过NPC的定向转运？(2)mRNA和ncRNA 出口途径是一体化的还是不同的？(3)RNA加工和输出是否通过共享的RBP进行协调 mRNP和ncRNP之间的关系通过解决这些问题，我们希望提供一个分子框架， 描述了Dbp 5和其他RBP如何参与，修改和指导核RNA加工和输出。这些 数据对于理解RNP通过NPC的流量以匹配蜂窝需求以及如何改变 这个突变过程导致疾病。此外，这些结果将有助于理解和 在死亡盒蛋白质，RNA运输和基因表达领域的方法，从而从根本上 为RNA生物学的研究做出了贡献。