Five Proteins of Laodelphax striatellus Are Potentially Involved in the Interactions between Rice Stripe Virus and Vector

Shuo Li,Ruyi Xiong,Xifeng Wang,Yijun Zhou,Vladimir N Uversky

doi:10.1371/journal.pone.0026585

Abstract

Rice stripe virus (RSV) is the type member of the genus Tenuivirus, which relies on the small brown planthopper (Laodelphax striatellus Fallén) for its transmission in a persistent, circulative-propagative manner. To be transmitted, virus must cross the midgut and salivary glands epithelial barriers in a transcytosis mechanism where vector receptors interact with virions, and as propagative virus, RSV need utilize host components to complete viral propagation in vector cells. At present, these mechanisms remain unknown. In this paper, we screened L. striatellus proteins, separated by two-dimensional electrophoresis (2-DE), as potential RSV binding molecules using a virus overlay assay of protein blots. The results, five L. striatellus proteins that bound to purified RSV particles in vitro were resolved and identified using mass spectrometry. The virus-binding capacities of five proteins were further elucidated in yeast two-hybrid screen (YTHS) and virus-binding experiments of expressed proteins. Among five proteins, the receptor for activated protein kinase C (RACK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH3) did not interact with RSV nucleocapsid protein (NCP) in YTHS and in far-Western blot, and three ribosomal proteins (RPL5, RPL7a and RPL8) had specific interactions with RSV. In dot immunobinding assay (DIBA), all five proteins were able to bind to RSV particles. The five proteins' potential contributions to the interactions between RSV and L. striatellus were discussed. We proposed that RACK and GAPDH3 might be involved in the epithelial transcytosis of virus particles, and three ribosomal proteins probably played potential crucial roles in the infection and propagation of RSV in vector cells.

Highlights

Rice stripe virus (RSV), the type member of the genus Tenuivirus, was first reported in Japan in 1975 [1] and is currently present in many East Asian countries, including China
A virus overlay assay was applied to ascertain whether specific binding of RSV particles to immobilized L. striatellus proteins would occur
The results showed that yeast cells cotransformed with pGBK-RPL5/pGAD-nucleocapsid protein (NCP), pGBK-r-protein L7a (RPL7a)/pGAD-NCP and pGBK-r-protein L8 (RPL8)/pGAD-NCP as positive controls as were able to grow on selective medium (SD/–Ade/–His/–Leu/–Trp supplemented with X-a-gal) (Fig. 3B), which indicated that specific interactions occurred between three proteins (RPL5, RPL7a and RPL8) of L. striatellus and RSV-NCP in the yeast two-hybrid system

Summary

Introduction

Rice stripe virus (RSV), the type member of the genus Tenuivirus, was first reported in Japan in 1975 [1] and is currently present in many East Asian countries, including China. RSV has been reported to cause severe disease in rice fields in China in recent years [2]. Nymphs all can transmit virus, while L. striatellus nymphs were reported as more efficient vectors than adults, and females as more efficient vectors than males for RSV transmission [3]. It is crucial for disease control to research the mechanisms how RSV is transmitted by L. striatellus. The molecular interaction mechanisms between RSV and vector remain unclear

Methods

Results

Conclusion