An insect cell line derived from the small brown planthopper supports replication of rice stripe virus, a tenuivirus

A cell line from the small brown planthopper (SBPH; Laodelphax striatellus) was established to study replication of rice stripe virus (RSV), a tenuivirus. The SBPH cell line, which had been subcultured through 30 passages, formed monolayers of epithelial-like cells. Inoculation of cultured vector cells with RSV resulted in a persistent infection. During viral infection in the SBPH cell line, the viral non-structural protein NS3 co-localized with the filamentous ribonucleoprotein particles of RSV, as revealed by electron and confocal microscopy. The knockdown of NS3 expression due to RNA interference induced by synthesized double-stranded RNAs from the NS3 gene significantly inhibited viral infection in the SBPH cell line. These results demonstrated that NS3 of RSV might be involved in viral replication or assembly. The persistent infection of the SBPH cell line by RSV will enable a better understanding of the complex relationship between RSV and its insect vector.