Studies On The Effect Of Dufulin In PVX Infection And Selecting Interaction Proteins With Pathogenic Factor P25

Dufulin is a new type of antiviral agent in plant crops,which is independently invented in China.Dufulin is widely used to prevent and control Southern Rice Black-streaked Dwarf Virus(SRBSDV)in rice.In the study of anti-SRBSDV,it it reported that dufulin has a strong absorbability in plants,and interacts with the coat protein(CP)of SRBSDV to destroy the outer shell and prevent the viral proliferation.Furthermore,Dufulin activates the downstream plant defense pathway by inducing the salicylic acid signal to improves the systemic disease resistance of crops,thereby showing antiviral activity.Potato virus x(PVX)is a representative member of Potexvirus.The genome consists of a positive single-stranded RNA molecule of approximately 6.4 kbp in length.The genome of PXV has five open reading frames(ORFs),and encodes the 166 k Da of RNA-dependent RNA polymerase(Rd Rp),25 k Da of TGBp1,12 k Da TGBp2,8 k Da TGBp3 and 25 k Da viral coat protein.Under natural conditions,PVX mainly relies on mechanical rub for propagation,which often mixed infects with other plant viruses(such as potato virus Y,PVY),then causing serious viral disease to crops.In this study,relevant work on whether dufulin has a preventive effect on PVX infection is conducted.First,the healthy N.benthamiana plants were pretreated with dufulin,with water treatment as a control.Green fluorescently labeled PVX-GFP was inoculated after 2days' treatment.The development of viral symptom was delayed on the dufulin pretreated plant,and the accumulations of PVX in the dufulin pretreated plants were significantly reduced in Real-time Quantitative PCR and Western Blot assay.It indicates that dufulin has the preventive effect on PVX infection.However,when treating the PVX-infected plants with dufulin,the experimental results show that there was no significant change in the accumulation of virus.It indicated that the healing effect of dufulin on PVX is not obvious.In order to solve the problem of curing PVX infection,the proteins interacting with PVX virulence factor p25,which were used to inhibit the function of p25,are screened by GFP magnetic co-precipitation.After mass spectrometry identification,20 candidate proteins that may interact with the pathogenic factor p25 are initially selected for further investigation.Bimolecular fluorescence complementation(Bi FC)and virus-induced gene silencing(VIGS)were used to investigate the role of SGS3 gene during the PVX infection.In summary,this work studies on the effect of antiviral agent dufulin during PVX infection,and clarifies that it has a preventive effect on PVX infection,which provides a biological basis for the further investigation of the mechanism of dufulin preventing PVX infection.Meanwhile,20 candidate proteins interacting with PVX virulence factor p25 are screened by GFP magnetic co-precipitation,which lays a foundation for the subsequent study to hinder p25 function from protein-protein interaction.