Hierarchical antiviral immunity in disease vector mosquitoes

 描述（由申请人提供）：虽然关于哺乳动物小RNA途径在抗病毒防御中的作用仍存在许多问题，但很明显，无脊椎生物中保守的抗病毒沉默途径的存在在蚊媒病毒性疾病的传播中起着重要作用。尽管小干扰RNA（siRNA）途径似乎在无脊椎生物体中提供主要的抗病毒免疫应答，但几条证据表明疾病媒介蚊子中存在的体细胞piwi相互作用RNA（皮尔纳）途径具有抗病毒作用。首先，从各种蚊子细胞系和组织中描述的病毒RNA产生piRNA本身暗示了抗病毒功能。 其次，与感染病毒病原体的siRNA缺陷型突变果蝇相关的增强的疾病表型相反，由病毒衍生的piRNA指导的抗病毒免疫应答调节siRNA缺陷型突变型蚊子细胞系中甲病毒感染的致病性。相反，已经显示敲低蚊子细胞中皮尔纳途径的组分增强甲病毒复制。因此，我们的研究计划被设计为测试存在于蚊子载体的索马中的非经典皮尔纳途径与小干扰RNA（siRNA）途径同时作用以形成协调的冗余抗病毒防御的假设。基于我们实验室先前的研究，疾病媒介中的分层抗病毒免疫模型为定义病毒皮尔纳产生的生物源途径、剖析皮尔纳和siRNA途径对抗病毒免疫和基因组完整性的相对贡献的实验提供了框架。，并评估操纵内源性皮尔纳簇作为广谱控制策略的潜力。

 DESCRIPTION (provided by applicant): While many questions remain regarding the role of mammalian small RNA pathways in antiviral defense, it is clear that the presence of conserved antiviral silencing pathways in invertebrate organisms plays an important role in the transmission of mosquito-borne viral diseases. Although the small interfering RNA (siRNA) pathway appears to provide the primary antiviral immune response in invertebrate organisms, several lines of evidence suggest an antiviral role for a somatic piwi-interacting RNA (piRNA) pathway present in disease vector mosquitoes. First, the production of piRNAs from viral RNAs described in various mosquito cell lines and tissues is itself suggestive of an antiviral function. Second, in contrast to the enhanced disease phenotype associated with siRNA-deficient mutant flies infected with viral pathogens, an antiviral immune response directed by virus-derived piRNAs modulates the pathogenicity of alphavirus infections in siRNA-deficient mutant mosquito cell lines. Conversly, knocking down components of the piRNA pathway in mosquito cells has been shown to enhance alphavirus replication. Thus, our research plan is designed to test the hypothesis that a non-canonical piRNA pathway present in the soma of mosquito vectors is acting concurrently with the small interfering RNA (siRNA) pathway to form a coordinated, redundant antiviral defense. A model of hierarchical antiviral immunity in disease vectors, based on previous studies in our laboratory, provides a framework for experiments to define the biogenic pathway of viral piRNA production, dissect the relative contributions of the piRNA and siRNA pathways to antiviral immunity and genome integrity, and evaluate the potential of manipulating endogenous piRNA clusters as a broad-spectrum control strategy.