中文摘要：

水稻瘤矮病毒（Ricegall dwarf virus,RGDV）属呼肠孤病毒科（Reoviridae）植物呼肠孤病毒属（Phytoreovirus），由介体电光叶蝉（Recilia dorsalis）以持久增殖型方式传播，其基因组第12条片段编码的非结构蛋白（nonstructural protein,Pns12）是提供病毒复制和子代病毒粒体装配场所——病毒原质（viroplasm）的组分之一。为了明确Pns12在RGDV侵染介体电光叶蝉培养细胞中的功能，本研究通过原核表达的Pns12蛋白免疫注射兔（Oryctolagus cuniculus），制备Pns12抗体，并应用免疫荧光标记和RNA干扰（RNA interference,RNAi）技术研究Pns12在介体培养细胞内的定位和参与病毒原质形成的过程。共聚焦显微镜观察到，病毒侵染的细胞中，与荧光素交联的Pns12抗体特异地标记在病毒原质上。干扰Pns12蛋白表达后，可有效地阻碍病毒原质的形成、子代病毒粒体的组装和病毒非结构蛋白Pns12和外壳蛋白P8蛋白的表达，表明Pns12作为病毒原质的组分参与了RGDV在介体培养细胞内的复制。也表明，Pns12可作为理想的靶标用于阻断电光叶蝉携带和传播RGDV。

英文摘要：

Rice gall dwarf virus（RGDV）, the genus Phytoreovirus in the family Reoviridae, is transmitted by the leafhopper vector（Recilia dorsalis） in a persistent-propagative manner. Nonstructural protein（Pns12）, encoded by segment 12 of RGDV, is one of the components of viroplasm which is the site for viral replication and assembly of progeny virons during viral infection in its insect vector cells. In this study, to investigate the functional role of Pns12 in the formation of viroplasm in its insect vector cells, the polyclonal antibody against Pns12 was prepared and purified, then conjugated to fluorescein isothiocyanate. The immunoglobulin G（IgG） of P8 was purified and conjugated to rhadamine. Immunofluorescence microscopy demonstrated that Pns12 antibodies specifically distributed in the viroplasm matrix during RGDV infection in the vector cells in monolayers （VCMs）, while outer capsid protein P8 were accumulated at the periphery of the viroplasm. The viroplasm increased in size over time. Knockdown of Pns12 by RNA interference （RNAi） induced by dsRNAs, targeting Pns12 gene of RGDV, significantly inhibited the formation of viroplasm compared with＆amp;nbsp;dsGFP, suggesting that RGDV replication was inhibited. Western blot showed that viral Pns12 and P8 expression reduced in the VCMs treated with dsPns12. Thus, the present study indicated that Pns12 of RGDV played an important role in viroplasm formation and viral replication in its insect vector cells. RNAi induced by dsRNAs derived from the viral genes of viroplasm matrix protein may be an ideal tool for inhibiting the infection and transmission of RGDV by leafhopper vectors.