Autophagy mechanism of coronaviral infection: Lessons from enteroviruses

冠状病毒感染的自噬机制：肠道病毒的教训

• 批准号: RGPIN-2022-02979
• 负责人: Luo, Honglin
• 金额: $ 2.91万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761963
• 关键词: Autophagy; mechanism; coronaviral; infection; Lessons

The long-term objective of my research program is to understand the molecular basis of how positive RNA viruses hijack the host cellular machinery to achieve successful infection. Positive-strand RNA viruses, including enteroviruses (EVs) and coronaviruses (CoVs), cover more than one-third of all virus genera and infect a wide range of hosts, including plants, animals, and humans. The previous NSERC Discovery Grant allowed us to make substantial progress towards understanding the underlying mechanisms by which Coxsackievirus (an EV) has evolved to exploit the host recycling system to support its lifecycle. In this renewal application, I propose to extend our research to study the interaction between CoVs and autophagy, a "self-eating" process in cells by which cells recycle damaged proteins and/or organelles. CoVs are a group of single-stranded RNA viruses covered by crown-like protein spikes, which can infect humans and a variety of animals, and cause a range of disorders from asymptomatic to lethal infection. My hypothesis is that similar to EVs, CoVs subvert the host autophagy machinery to ensure successful infection by enhancing viral replication and through preventing the clearance of viral components and/or particles. This hypothesis is based on our novel observations that (1) CoVs induce autophagy through a pathway independent of enzymes known to be required for traditional autophagy; and (2) CoV-encoded proteases target a number of host proteins involved in autophagy regulation for degradation. Despite these findings, the detailed mechanisms of how CoVs hijack the host autophagy pathway and the functional consequence of the cleavage of autophagic proteins remain unclear. To test this hypothesis, we will combine the use of cutting-edge proteomics and imaging approaches with conventional molecular and cellular technologies to study how CoVs manipulate the autophagy pathway and to identify the critical enzymes and target proteins within the autophagy pathway that regulates CoV infection. Our experience in investigating enteroviral subversion of the autophagy pathway places us in a unique position to understand the interplay between host autophagy and CoVs. This research, exploring a novel autophagy-based viral mechanism, will fill a key knowledge gap in our understanding of the mechanisms underlying effective CoV infection of host cells. Knowledge acquired from this research will also have broader implications for the study of host-pathogen interactions of other viruses in the same family. The proposed research program will also benefit Canada and the Canadian economy by training 3 PhD graduate and 5 undergraduate students in natural science for future careers in academic research and teaching institutions, medical laboratories, and biotechnology companies.

我的研究计划的长期目标是了解RNA阳性病毒如何劫持宿主细胞机制以实现成功感染的分子基础。阳性链RNA病毒，包括肠病毒（EV）和冠状病毒（COVS），覆盖了所有病毒属的三分之一以上，并感染了包括植物，动物和人类在内的广泛宿主。以前的NSERC Discovery Grant使我们能够取得重大进展，以了解Coxsackievivirus（AN EV）进化以利用宿主回收系统来支持其生命周期的基本机制。在此续签应用中，我建议扩展我们的研究以研究COVS与自噬之间的相互作用，这是细胞中细胞回收受损蛋白质和/或细胞器的细胞中的“自食”过程。 COV是一组单链RNA病毒，被冠状蛋白峰覆盖，可感染人类和各种动物，并引起一系列疾病，从无症状到致死感染。我的假设是，与电动汽车相似，COV颠覆了宿主自噬机制，以通过增强病毒复制和防止病毒成分和/或颗粒的清除来确保成功感染。该假设基于我们的新观察结果，即（1）COV通过独立于传统自噬所需的酶的途径诱导自噬； （2）COV编码的蛋白酶的目标是许多参与自噬调节降解的宿主蛋白。尽管有这些发现，但COVS如何劫持宿主自噬途径的详细机制以及自噬蛋白裂解的功能后果仍不清楚。为了检验这一假设，我们将将尖端蛋白质组学和成像方法的使用与常规分子和细胞技术相结合，以研究COV如何操纵自噬途径，并确定临界酶和靶向自噬途径中调节COV感染的自噬途径中的蛋白质。我们调查自噬途径的肠病毒颠覆的经验使我们处于独特的位置，以了解宿主自噬与COV之间的相互作用。这项研究探索了一种新型的基于自噬的病毒机制，将填补我们对宿主细胞有效COV感染的机制的关键知识差距。从这项研究中获得的知识也将对同一家族其他病毒的宿主病原体相互作用的研究具有更广泛的影响。拟议的研究计划还将通过培训3级博士研究生和5位自然科学的本科生，从而使加拿大和加拿大经济受益匪浅，从而在学术研究和教学机构，医疗实验室和生物技术公司中为未来的职业生涯。