The Vitellogenin Receptor has an Essential Role in Vertical Transmission of Rice Stripe Virus during Oogenesis in the Small Brown Plant Hopper.

BACKGROUND: The small brown planthopper (SBPH), Laodelphax striatellus Fallén, is one of the most destructive pests on rice. This pest transmits rice stripe virus (RSV) both horizontally and vertically, leading to major yield and economic losses in rice production. However, the way that RSV particles enter oocytes of SBPH remains largely unknown. Thus, identification of key factors involved in the interaction between SBPH and RSV in the ovary is crucial.

RESULTS: Transcriptome of non-viruliferous (NV) or high viruliferous (HV) SBPH ovaries at 24 h and 48 h of emergence was sequenced. Differentially expressed genes analysis showed that vitellogenin receptor (VgR) was significantly high expressed in the ovary of the HV SBPH strains compared to NV strains. qRT-PCR showed that LsVgR was high expressed in ovaries of female adults and maintained a high level of expression at the early stage of ovary development. By using RNA interference (RNAi), the expression of LsVgR in ovary of HV strain was significantly decreased by 98.1%. RSV titer was reduced by 60.9% as quantified by viral RNA3 intergenic region and the transcripts of nucleocapsid protein gene (CP) reduced by 46.3%. The numbers of offspring hatched were significantly reduced in dsRNA-treated groups. The transcripts of CP were not affected by silencing LsVgR, whereas the abundance of RNA dependent RNA Polymerase (RdRp) increased by 15-fold in the member of surviving progenies.

CONCLUSION: Our results suggest that vitellogenin receptor participates in regulating RSV replication during oogenesis. This article is protected by copyright. All rights reserved.