Understanding the reprogramming of host mRNA translation during calicivirus infection

了解杯状病毒感染期间宿主 mRNA 翻译的重编程

• 批准号: BB/N000943/1
• 负责人: Nicolas Locker
• 金额: $ 44.01万
• 依托单位: University of Surrey
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FN000943%2F1
• 关键词: Understanding; reprogramming; host; mRNA; translation

Our overarching aim is to understand the mechanism by which a group of poorly characterised, yet important viruses, regulate host gene expression to modulate how cells respond to viral infection Cells within the body respond to environmental stimuli and pathogen infection in many ways, the most common of which is via the regulation of cellular gene expression. The expression of the information stored in our genes is tightly controlled at numerous levels, to ensure that the correct protein is produced at the right time and quantity. First, the genetic information encoded in our DNA is converted into messenger RNA (mRNA), via a process called transcription. The mRNA is then "translated" into proteins by structures referred to as ribosomes, assisted by proteins called initiation factors. eIF4E is one of these proteins and its key role is to direct the ribosomes and other proteins to the mRNA. This process is called translation and the synthesised proteins make our cells what they are, defining their properties and functions. Importantly, changes to the proteins in our cells also help to fight against invading pathogens such as viruses. While viruses can infect most organisms and cause severe damage, they consist primarily of RNA or DNA enclosed in a protein coat and lack the factors required for replication and dissemination. They are therefore dependent on the host cell resources to produce viral proteins. Thus, many viruses have developed strategies that regulate the function of the host protein synthesis machinery, often leading to preferentially translation of viral mRNAs. Caliciviruses are a family of small viruses that can cause diseases both in humans and animals. In humans they primarily cause gastroenteritis. While the human norovirus, a calicivirus, does not grow well in cell culture, murine norovirus, a mouse homologue, acts as model with which to study many aspects of calicivirus biology in the laboratory. It represents an excellent model to dissect how viruses affect the translation of host cell proteins. Using this model we have previously made a number of significant advances in the understanding of how the caliciviruses produce viral proteins. We found that a virus-encoded protein, called VPg, is essential for the translation of viral mRNA as it coordinates the recruitment of host proteins to the viral RNA. We also showed that calicivirus infection modulates the composition and activity of the host translation machinery. However, we still know very little about how pathogens in general, and caliciviruses in particular, modulate the translation of host mRNAs during infection. This is important because understanding the modulation of specific host mRNA translation by viruses can reveal how viruses manipulate the organism's response to infection. Our hypothesis is that caliciviruses alter the translation of specific mRNAs in the infected host to regulate antiviral gene expression, and that they do so by modulating the translation factor eIF4E. Therefore, our objectives are to use high-throughput sequencing and biochemical methods to 1- characterize how the viral infection alters the profile of mRNAs that are translated by the infected host and 2- to understand how the activity of eIF4E is regulated by caliciviruses during this process. If we can fully understand how caliciviruses control the activity of translation factors and reprogramme the host protein synthesis, we can identify ways to inhibit virus replication. Therefore, our work will aid in the development of novel antiviral therapies for this important group of viruses, and perhaps other viruses that regulate translation. Understanding the fundamental mechanisms of gene regulation is important not only for virologists but also for broader academic communities. By advancing our basic knowledge of translational control we may understand better several pathologies that are linked to modulation of eIF4E activity, such as cancer and diabetes.

我们的首要目标是了解一组特征不明确但重要的病毒调节宿主基因表达以调节细胞对病毒感染的反应的机制体内细胞以多种方式对环境刺激和病原体感染做出反应，最常见的是其中是通过细胞基因表达的调节。存储在我们基因中的信息的表达在多个层面上受到严格控制，以确保在正确的时间和数量产生正确的蛋白质。首先，DNA 中编码的遗传信息通过转录过程转化为信使 RNA (mRNA)。然后，在称为起始因子的蛋白质的协助下，mRNA 通过称为核糖体的结构“翻译”为蛋白质。 eIF4E 是这些蛋白质之一，其关键作用是将核糖体和其他蛋白质引导至 mRNA。这个过程称为翻译，合成的蛋白质使我们的细胞成为它们的样子，定义它们的特性和功能。重要的是，细胞中蛋白质的变化也有助于对抗病毒等入侵病原体。虽然病毒可以感染大多数生物体并造成严重损害，但它们主要由包裹在蛋白质外壳中的 RNA 或 DNA 组成，缺乏复制和传播所需的因子。因此，它们依赖宿主细胞资源来产生病毒蛋白。因此，许多病毒已经开发出调节宿主蛋白质合成机制功能的策略，通常导致病毒 mRNA 的优先翻译。杯状病毒是一类小病毒，可引起人类和动物疾病。在人类中，它们主要引起胃肠炎。虽然人类诺如病毒（杯状病毒）在细胞培养中生长不佳，但鼠诺如病毒（小鼠同源物）可以作为模型，在实验室中研究杯状病毒生物学的许多方面。它代表了一个很好的模型来剖析病毒如何影响宿主细胞蛋白质的翻译。使用这个模型，我们之前在了解杯状病毒如何产生病毒蛋白方面取得了许多重大进展。我们发现，一种名为 VPg 的病毒编码蛋白对于病毒 mRNA 的翻译至关重要，因为它协调将宿主蛋白招募到病毒 RNA 中。我们还表明杯状病毒感染调节宿主翻译机器的组成和活性。然而，我们对一般病原体，特别是杯状病毒在感染过程中如何调节宿主 mRNA 的翻译仍然知之甚少。这很重要，因为了解病毒对特定宿主 mRNA 翻译的调节可以揭示病毒如何操纵生物体对感染的反应。我们的假设是杯状病毒改变受感染宿主中特定 mRNA 的翻译来调节抗病毒基因表达，并且它们通过调节翻译因子 eIF4E 来实现这一点。因此，我们的目标是使用高通量测序和生化方法来 1- 表征病毒感染如何改变受感染宿主翻译的 mRNA 的概况，2- 了解杯状病毒在此期间如何调节 eIF4E 的活性过程。如果我们能够充分了解杯状病毒如何控制翻译因子的活性并重新编程宿主蛋白质的合成，我们就可以找到抑制病毒复制的方法。因此，我们的工作将有助于针对这一类重要病毒以及其他调节翻译的病毒开发新型抗病毒疗法。了解基因调控的基本机制不仅对病毒学家很重要，对更广泛的学术界也很重要。通过提高我们对翻译控制的基础知识，我们可以更好地了解与 eIF4E 活性调节相关的几种病理学，例如癌症和糖尿病。

项目成果

Murine Norovirus Infection Results in Anti-inflammatory Response Downstream of Amino Acid Depletion in Macrophages

鼠诺如病毒感染导致巨噬细胞氨基酸消耗下游的抗炎反应

• DOI: http://dx.10.1128/jvi.01134-21
• 发表时间: 2021
• 期刊: Journal of Virology
• 影响因子: 5.4
• 作者: Brocard M

Norovirus infection results in eIF2a independent host translation shut-off and remodels the G3BP1 interactome evading stress granule formation.

诺如病毒感染导致 eIF2a 独立的宿主翻译关闭，并重塑 G3BP1 相互作用组以逃避应激颗粒的形成。

• DOI: http://dx.10.1371/journal.ppat.1008250
• 发表时间: 2020
• 期刊: PLoS pathogens
• 影响因子: 6.7
• 作者: Brocard M

Infectious bronchitis virus regulates cellular stress granule signaling

传染性支气管炎病毒调节细胞应激颗粒信号传导

• DOI: http://dx.10.1101/819482
• 发表时间: 2019
• 作者: Brownsword M

Norovirus infection results in eIF2a independent host translation shut-off and remodels the G3BP1 interactome evading stress granule formation.

诺如病毒感染导致 eIF2a 独立的宿主翻译关闭，并重塑 G3BP1 相互作用组以逃避应激颗粒的形成。

• DOI: http://dx.10.17863/cam.48874
• 发表时间: 2020
• 作者: Brocard M

Murine Norovirus Infection Results in Anti-inflammatory Response Downstream of Amino Acid Depletion in Macrophages

鼠诺如病毒感染导致巨噬细胞氨基酸消耗下游的抗炎反应

• DOI: http://dx.10.1128/jvi.01134-21.4
• 发表时间: 2021
• 期刊: JOURNAL OF VIROLOGY
• 作者: Brocard Michele