水稻齿叶矮缩病毒非结构蛋白Pns7形成伸出昆虫细胞膜的纤维丝状结构

Rice ragged stunt virus (RRSV), a member of the genus Oryzavirus, is one of the most economically important pathogens of rice in China. At present, the function of viral nonstructural protein Pns7 of RRSV is unknown. In this study, the RT-PCR product of Pns7 gene was recombinated into the Gateway prokaryotic expression vector pDEST-17 and then transformed into component cell Escherichia coli Rosetta. The expression of Pns7 proteins were induced by IPTG treatment. We obtained antisera against Pns7 by injected the expressed Pns7 proteins into rabbit. Western blot analysis indicated that the antisera against Pns7 could specifically recognize Pns7 proteins in diseased plants. Expression of RRSV Pns7 in insect cell Sf9 by a recombinant baculovirus resulted in the formation of filamentous structures which could protrude from the cell surface, revealed by immunofluorescence microscopy with prepared Pns7 antibodies. Furthermore, the protrusion of filaments from cell surface induced by Pns7 was accompanied by actin-based cellular protrusion. Interestingly, the expression of Pns7 led to the extension of actin-based cellular protrusion, and thus, to the alteration of cell morphology. Together, our results suggested that RRSV Pns7 might be involved in viral spread in host plant or vector insect.