Elucidation of the pathogenesis mechanism of viroids

阐明类病毒的发病机制

• 批准号: RGPIN-2017-04027
• 负责人: Perreault, JeanPierre
• 金额: $ 3.64万
• 依托单位: Université de Sherbrooke
• 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=744356
• 关键词: Elucidation; pathogenesis; mechanism; viroids

Elucidation of the pathogenesis mechanism of viroids Viroids infect higher plants and cause diseases that result in significant damages in agriculture, accounting for the loss of several billion dollars every year. They affect food, ornamental and industrial plants worldwide. Currently, there are 32 known species of these pathogens, all of which are composed of an unencapsidated, circular, single-stranded, non-coding RNA that is between 246-401 nucleotides (nt) long. These infectious RNA species replicate through an RNA-dependent rolling circle mechanism. Although they do not code for any known protein, viroids can obviate a plant's cellular defense mechanism and act as parasites, making them the smallest self-replicating genetic elements identified to date. RNA interference plays a central role in the pathogenesis of viroids so we propose to study the quasispecies nature of these pathogens. RNA interference elicits pathogenesis through base-pairing of vd-sRNA on host mRNAs. Consequently, it is clearly important to develop a method for following and understanding the evolution of the different haplotypes after infection, in addition to further strengthen our understanding of the related RNA silencing mechanism. Our long-term goal is to learn as much as possible on the biology of viroid species as a way of becoming a leader in the development of optimally resistant cultivars. In order to progress in this direction, our specific objectives are:1. To study the behavior of the quasispecies under different growing conditions through time; and,2. To identify the vd-sRNAs, and their respective host targets, as well as the plants' endogenous microRNAs that are affected during viroid infection.All experiments will be performed with plant cultivars that are of importance for the Canadian agricultural sector. We expect to elucidate the definition of quasispecies under different growing conditions, and to highlight genes that play a key role in the pathogenesis of viroids in both tomato and grapevine. Our results should set the foundation for the elucidation of viroid pathogenesis, and should help finding a cure for these infections in addition to encouraging the use of viroids to advance the boundaries of life sciences.

类病毒侵染高等植物引起的病害给农业生产造成重大损失，每年造成数十亿美元的经济损失。它们影响全世界的食用植物、观赏植物和工业植物。目前，已知有32种这些病原体，所有这些病原体都由长度在246-401个核苷酸（nt）之间的未标记的环状单链非编码RNA组成。这些感染性RNA种类通过RNA依赖性滚环机制复制。虽然它们不编码任何已知的蛋白质，但类病毒可以破坏植物的细胞防御机制并作为寄生虫，使它们成为迄今为止发现的最小的自我复制遗传元件。RNA干扰在类病毒的发病机制中起着核心作用，因此我们建议研究这些病原体的准种性质。RNA干扰通过vd-sRNA在宿主mRNA上的碱基配对来诱导发病。因此，除了进一步加强我们对相关RNA沉默机制的理解之外，开发一种跟踪和理解感染后不同单倍型进化的方法显然是重要的。我们的长期目标是尽可能多地了解类病毒物种的生物学，成为开发最佳抗性品种的领导者。为了朝着这个方向前进，我们的具体目标是：1。研究准种在不同生长条件下随时间的行为。为了鉴定vd-sRNA及其各自的宿主靶标，以及在类病毒感染过程中受影响的植物内源性microRNA，所有实验将使用对加拿大农业部门重要的植物品种进行。我们希望阐明准种的定义在不同的生长条件下，并强调在番茄和葡萄类病毒的发病机制中发挥关键作用的基因。我们的研究结果应该为阐明类病毒的发病机制奠定基础，并有助于找到治疗这些感染的方法，同时鼓励使用类病毒来推进生命科学的边界。