Blair Carol D, Olson Ken E
Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO 80523, USA.
Viruses. 2015 Feb 17;7(2):820-43. doi: 10.3390/v7020820.
RNA interference (RNAi) was shown over 18 years ago to be a mechanism by which arbovirus replication and transmission could be controlled in arthropod vectors. During the intervening period, research on RNAi has defined many of the components and mechanisms of this antiviral pathway in arthropods, yet a number of unexplored questions remain. RNAi refers to RNA-mediated regulation of gene expression. Originally, the term described silencing of endogenous genes by introduction of exogenous double-stranded (ds)RNA with the same sequence as the gene to be silenced. Further research has shown that RNAi comprises three gene regulation pathways that are mediated by small RNAs: the small interfering (si)RNA, micro (mi)RNA, and Piwi-interacting (pi)RNA pathways. The exogenous (exo-)siRNA pathway is now recognized as a major antiviral innate immune response of arthropods. More recent studies suggest that the piRNA and miRNA pathways might also have important roles in arbovirus-vector interactions. This review will focus on current knowledge of the role of the exo-siRNA pathway as an arthropod vector antiviral response and on emerging research into vector piRNA and miRNA pathway modulation of arbovirus-vector interactions. Although it is assumed that arboviruses must evade the vector's antiviral RNAi response in order to maintain their natural transmission cycles, the strategies by which this is accomplished are not well defined. RNAi is also an important tool for arthropod gene knock-down in functional genomics studies and in development of arbovirus-resistant mosquito populations. Possible arbovirus strategies for evasion of RNAi and applications of RNAi in functional genomics analysis and arbovirus transmission control will also be reviewed.
18 多年前就已表明，RNA干扰（RNAi）是一种可在节肢动物载体中控制虫媒病毒复制和传播的机制。在此期间，对RNAi的研究确定了节肢动物中这种抗病毒途径的许多组成部分和机制，但仍有一些未探索的问题。RNAi是指RNA介导的基因表达调控。最初，该术语描述了通过引入与要沉默的基因具有相同序列的外源双链（ds）RNA来沉默内源基因。进一步的研究表明，RNAi包括由小RNA介导的三种基因调控途径：小干扰（si）RNA、微小（mi）RNA和Piwi相互作用（pi）RNA途径。外源（exo-）siRNA途径现在被认为是节肢动物主要的抗病毒先天免疫反应。最近的研究表明，piRNA和miRNA途径可能在虫媒病毒与载体的相互作用中也发挥重要作用。本综述将重点关注关于exo-siRNA途径作为节肢动物载体抗病毒反应的作用的当前知识，以及对载体piRNA和miRNA途径调节虫媒病毒与载体相互作用的新兴研究。尽管假定虫媒病毒必须逃避载体的抗病毒RNAi反应才能维持其自然传播周期，但实现这一目标的策略尚未明确界定。RNAi也是功能基因组学研究中节肢动物基因敲除以及抗虫媒病毒蚊虫种群开发的重要工具。还将综述虫媒病毒逃避RNAi的可能策略以及RNAi在功能基因组学分析和虫媒病毒传播控制中的应用。
