title: Small interfering RNA pathway modulates persistent infection of a plant virus in its insect vector.
abstract: Plant reoviruses, rhabdoviruses, tospoviruses, and tenuiviruses are transmitted by insect vectors in a persistent-propagative manner. How such persistent infection of plant viruses in insect vectors is established and maintained remains poorly understood. In this study, we used rice gall dwarf virus (RGDV), a plant reovirus, and its main vector leafhopper Recilia dorsalis as a virus-insect system to determine how the small interference (siRNA) pathway modulates persistent infection of a plant virus in its insect vector. We showed that a conserved siRNA antiviral response was triggered by the persistent replication of RGDV in cultured leafhopper cells and in intact insects, by appearance of virus-specific siRNAs, primarily 21-nt long, and the increased expression of siRNA pathway core components Dicer-2 and Argonaute-2. Silencing of Dicer-2 using RNA interference strongly suppressed production of virus-specific siRNAs, promoted viral accumulation, and caused cytopathological changes in vitro and in vivo. When the viral accumulation level rose above a certain threshold of viral genome copy (1.32 × 10(14) copies/μg insect RNA), the infection of the leafhopper by RGDV was lethal rather than persistent. Taken together, our results revealed a new finding that the siRNA pathway in insect vector can modulate persistent infection of plant viruses.
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Hanhong
authors: H
authors: Lan
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Haitao
authors: H
authors: Wang
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Qian
authors: Q
authors: Chen
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Hongyan
authors: H
authors: Chen
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Dongsheng
authors: D
authors: Jia
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Qianzhuo
authors: Q
authors: Mao
authors: Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors: Taiyun
authors: T
authors: Wei
mesh_terms: D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics* / Q000276:immunology; D056915:DNA Copy Number Variations; D016679:Genome, Viral; D006430:Hemiptera / Q000235:genetics* / Q000276:immunology / Q000821:virology; D054884:Host-Pathogen Interactions; D019476:Insect Proteins / Q000235:genetics* / Q000276:immunology; D007303:Insect Vectors / Q000235:genetics* / Q000276:immunology / Q000821:virology; D012275:Oryza / Q000821:virology; D010935:Plant Diseases / Q000821:virology; D020365:RNA Helicases / Q000235:genetics* / Q000276:immunology; D034741:RNA, Small Interfering / Q000235:genetics / Q000276:immunology; D012087:Reoviridae / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D014779:Virus Replication
chemical_list: D060565:Argonaute Proteins; D019476:Insect Proteins; D034741:RNA, Small Interfering; D020365:RNA Helicases