Nonstructural protein Pns4 of rice dwarf virus is essential for viral infection in its insect vector
- PDF / 2,123,750 Bytes
- 7 Pages / 595.276 x 793.701 pts Page_size
- 11 Downloads / 198 Views
RESEARCH
Open Access
Nonstructural protein Pns4 of rice dwarf virus is essential for viral infection in its insect vector Qian Chen, Linghua Zhang, Hongyan Chen, Lianhui Xie* and Taiyun Wei*
Abstract Background: Rice dwarf virus (RDV), a plant reovirus, is mainly transmitted by the green rice leafhopper, Nephotettix cincticeps, in a persistent-propagative manner. Plant reoviruses are thought to replicate and assemble within cytoplasmic structures called viroplasms. Nonstructural protein Pns4 of RDV, a phosphoprotein, is localized around the viroplasm matrix and forms minitubules in insect vector cells. However, the functional role of Pns4 minitubules during viral infection in insect vector is still unknown yet. Methods: RNA interference (RNAi) system targeting Pns4 gene of RDV was conducted. Double-stranded RNA (dsRNA) specific for Pns4 gene was synthesized in vitro, and introduced into cultured leafhopper cells by transfection or into insect body by microinjection. The effects of the knockdown of Pns4 expression due to RNAi induced by synthesized dsRNA from Pns4 gene on viral replication and spread in cultured cells and insect vector were analyzed using immunofluorescence, western blotting or RT-PCR assays. Results: In cultured leafhopper cells, the knockdown of Pns4 expression due to RNAi induced by synthesized dsRNA from Pns4 gene strongly inhibited the formation of minitubules, preventing the accumulation of viroplasms and efficient viral infection in insect vector cells. RNAi induced by microinjection of dsRNA from Pns4 gene significantly reduced the viruliferous rate of N. cincticeps. Furthermore, it also strongly inhibited the formation of minitubules and viroplasms, preventing efficient viral spread from the initially infected site in the filter chamber of intact insect vector. Conclusions: Pns4 of RDV is essential for viral infection and replication in insect vector. It may directly participate in the functional role of viroplasm for viral replication and assembly of progeny virions during viral infection in leafhopper vector. Keywords: Rice dwarf virus, Leafhopper vector, Pns4 minitubules, Viroplasm, RNA interference
Background Viruses in the family Reoviridae are thought to replicate and assemble within cytoplasmic, nonmembranous structures called viroplasms [1]. For animal reoviruses, including reoviruses, rotaviruses and bluetongue virus (BTV), viral dsRNA, mRNA and proteins, and host components such as ribosomes, protein-synthesis machinery and chaperones aggregate within the viroplasm matrix [1–4]. Furthermore, some host components such as ribosomes, membrane components, mitochondria and microtubules * Correspondence: [email protected]; [email protected] Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China
have been observed to accumulate at the periphery of the viroplasm matrix [1, 3, 4]. The host components at the periphery of the viroplasm may be utilized to facilitate viral replication and a
Data Loading...
