Molecular mechanisms regulating mRNA transport and local translation in neurons.

调节神经元中 mRNA 运输和局部翻译的分子机制。

• 批准号: MR/S000305/1
• 负责人: Andres Ramos
• 金额: $ 167.4万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FS000305%2F1
• 关键词: Molecular; mechanisms; regulating; mRNA; transport

The developing human brain must create short- and long-distance connections between dendrites and axons in a highly regulated fashion. The creation of new dendrites and the development and differentiation of synapses are an essential part of this process and require, in turn, the local translation of a large set of mRNAs. There is growing evidence that up to thousands of mRNAs are differentially translated in the dendritic compartment, thus making local translation a general and key process in neuronal development. Mistakes in the regulation of local mRNA translation lead to a range of developmental diseases and neuro-pathologies.Local mRNA translation requires the selective transport and locally regulated translation of the mRNAs and is mediated by multi-functional, multi-domain RNA-binding proteins that recognise sequences or structures in the mRNAs and act as adaptors for the molecular motors and the cellular degradation and translation machineries. Despite several of these proteins having been identified, we know very little of how they target the cognate mRNAs and interact with the cellular machineries at the molecular level. Also we know very little of how these proteins are regulated by specific signals.We work on IGF2 mRNA Binding Protein 1 (IMP1, also called Zipcode Binding Protein 1, ZBP1) as a paradigm for the RNA-binding proteins regulating local mRNA translation. IMP1 is a multi-functional, multi-domain RNA-binding protein that plays a key role in defining synaptic morphology in neurons and has a general function in regulating cell motility and differentiation. Functional information in fly, worm, chicken and mammals has shown that IMP1 regulates the transport and local translation of a number of different mRNAs, and has linked the protein to the transport of specific mRNAs (e.g. beta-actin) and to a well-defined regulatory mechanism that promotes local mRNA translation in response to signalling in neurons.The questions we are asking are how IMP1 and other protein regulators recognise a diverse set of RNA targets, and how RNA recognition is linked to mRNA transport. We want to know how the RNA-binding proteins interact with the cellular mRNA transport machineries and how their functions are regulated by signalling at the molecular level. In the longer term, we want to obtain a broader understanding of the function of these proteins in local mRNA translation, that include their capability to localizing multiple, functionally related, targets, as a prelude to study the synergies between the locally translated proteins. We will use structural and biophysical techniques to answer these questions in the IMP1 system and determine the molecular rules of IMP1 target recognition and of its regulation by signalling. Further, we will characterise IMP1 protein and RNA partners in neurons and use in cell transcriptome-wide assays to look at how IMP1 achieves the selection of the RNA targets in the cell, and to understand the RNA binding and re-modelling of the RNA is linked to the functional output. This work will provide a unique structural and molecular analysis of the functional interactions mediating local mRNA translation in mammals. The output will be used to inform the investigation of the function of IMP1 in processes linked to neuronal development and function, for example in dendritic arborisation and in the changes in synaptic morphology. Importantly, our understanding of IMP1 will provide tools and concepts for investigating other RNA-binding proteins with a vital role in neuronal functioning (e.g. Syncrip, FMRP and TDP43) that are linked to widespread and severe neuro-pathologies.

发育中的人类大脑必须以高度调控的方式在树突和轴突之间建立短距离和长距离的连接。新树突的产生以及突触的发育和分化是这一过程的重要组成部分，反过来又需要大量 mRNA 的本地翻译。越来越多的证据表明，多达数千个 mRNA 在树突区室中进行差异翻译，从而使局部翻译成为神经元发育中的普遍且关键的过程。局部 mRNA 翻译调节中的错误会导致一系列发育疾病和神经病理学。局部 mRNA 翻译需要 mRNA 的选择性运输和局部调节翻译，并由多功能、多结构域 RNA 结合蛋白介导，识别 mRNA 中的序列或结构，并充当分子马达以及细胞降解和翻译机器的适配器。尽管其中几种蛋白质已经被鉴定出来，但我们对它们如何靶向同源 mRNA 并在分子水平上与细胞机制相互作用知之甚少。此外，我们对这些蛋白质如何受特定信号的调节知之甚少。我们研究 IGF2 mRNA 结合蛋白 1（IMP1，也称为邮政编码结合蛋白 1，ZBP1）作为调节局部 mRNA 翻译的 RNA 结合蛋白的范例。 IMP1 是一种多功能、多结构域 RNA 结合蛋白，在定义神经元突触形态方面发挥关键作用，并在调节细胞运动和分化方面具有一般功能。苍蝇、蠕虫、鸡和哺乳动物的功能信息表明，IMP1 调节许多不同 mRNA 的运输和局部翻译，并将该蛋白质与特定 mRNA（例如 β-肌动蛋白）的运输和明确定义的 mRNA 联系起来。响应神经元信号传导促进局部 mRNA 翻译的调节机制。我们要问的问题是 IMP1 和其他蛋白质调节因子如何识别不同的 RNA 靶标，以及 RNA 识别如何与 mRNA 运输联系起来。我们想知道 RNA 结合蛋白如何与细胞 mRNA 转运机制相互作用，以及它们的功能如何通过分子水平的信号传导进行调节。从长远来看，我们希望更广泛地了解这些蛋白质在局部 mRNA 翻译中的功能，包括它们定位多个功能相关的靶标的能力，作为研究局部翻译蛋白质之间协同作用的前奏。我们将利用结构和生物物理技术来回答IMP1系统中的这些问题，并确定IMP1靶标识别及其信号传导调节的分子规则。此外，我们将表征神经元中的 IMP1 蛋白和 RNA 伴侣，并用于细胞转录组范围的检测，以了解 IMP1 如何实现细胞中 RNA 靶标的选择，并了解 RNA 的结合和 RNA 的重新建模。链接到功能输出。这项工作将为调节哺乳动物局部 mRNA 翻译的功能相互作用提供独特的结构和分子分析。输出结果将用于研究 IMP1 在与神经元发育和功能相关的过程中的功能，例如树突状树枝化和突触形态的变化。重要的是，我们对 IMP1 的理解将为研究其他在神经元功能中发挥重要作用的 RNA 结合蛋白（例如 Syncrip、FMRP 和 TDP43）提供工具和概念，这些蛋白与广泛且严重的神经病理学相关。

项目成果

Direct m6A recognition by IMP1 underlays an alternative model of target selection for non-canonical methyl-readers.

• DOI: 10.1093/nar/gkad534
• 发表时间: 2023-09-08
• 期刊: Nucleic acids research
• 影响因子: 14.9

The distinct RNA-interaction modes of a small ZnF domain underlay TUT4(7) diverse action in miRNA regulation

小 ZnF 结构域的独特 RNA 相互作用模式是 TUT4(7) 在 miRNA 调节中多种作用的基础

• DOI: 10.6084/m9.figshare.16912173
• 发表时间: 2021
• 作者: Chaves-Arquero B

Small molecule inhibitor of Igf2bp1 represses Kras and a pro-oncogenic phenotype in cancer cells.

• DOI: 10.1080/15476286.2021.2010983
• 发表时间: 2022
• 期刊: RNA biology
• 影响因子: 4.1
• 作者: Wallis N;Oberman F;Shurrush K;Germain N;Greenwald G;Gershon T;Pearl T;Abis G;Singh V;Singh A;Sharma AK;Barr HM;Ramos A;Spiegelman VS;Yisraeli JK
• 通讯作者: Yisraeli JK

The TH1 cell lineage-determining transcription factor T-bet suppresses TH2 gene expression by redistributing GATA3 away from TH2 genes.

• DOI: 10.1093/nar/gkac258
• 发表时间: 2022-05-06
• 期刊: NUCLEIC ACIDS RESEARCH
• 影响因子: 14.9
• 作者: Hertweck, Arnulf;Vila de Mucha, Maria;Barber, Paul R.;Dagil, Robert;Porter, Hayley;Ramos, Andres;Lord, Graham M.;Jenner, Richard G.
• 通讯作者: Jenner, Richard G.

The distinct RNA-interaction modes of a small ZnF domain underlay TUT4(7) diverse action in miRNA regulation.

• DOI: 10.1080/15476286.2021.1991169
• 发表时间: 2021-11-12
• 期刊: RNA biology
• 影响因子: 4.1
• 作者: Chaves-Arquero B;Collins KM;Christodoulou E;Nicastro G;Martin SR;Ramos A
• 通讯作者: Ramos A