Screening And Functional Study With Magnaporthe Oryzae Effector Suppressing Plant RNA Silencing

Magnaporthe oryzae is one of the most important pathogenicitiesof rice,has spreaded in the major rice growing regions in the world.The interaction between Magnaporthe oryzae and rice istypical,which is considered as a model pathogen in the research ofmolecular plant pathology.In the process of natural selection,plantgradually evolved adaptive immune system in order to resist theinvasion of pathogenic biology.The RNA silencing as one of the majorpathogen defense mechanism of plants, in order to deal with thisresistance mechanism of plants, many plant pathogens have evolvedcan offset, weaken or even avoid this ability to defenseresponse.Effector is a secreted protein produced after pathogensinvade the host plant,which can dispersed into plant cells in theinvasion sites.It can interact with its corresponding receptor rapid inorder to regulate the host immune response and lead to host plants ofsusceptible or resistant.This research utilize the effectors of Magnaporthe oryzae as the research object,screening and functionalidentification with effectors suppressed RNA silencing.The resultswere as follows:1.21Magnaporthe oryzae effectors gene were amplified by PCRand cloned into pGDR vector.2.Base on RNA silencing system using16C N.benthamiana asmaterials,21candidate effectors genes were screened for RNAsilencing suppressors,we found three effector genes has a obviouseffect to suppress gene silencing.However,the result are to be furtherverified.3.Through the observation of confocal laser scanning microscope,we found two effector genes appeared irregularly localization and oneeffector gene localizated in the cytoplasmic membrane in riceprotoplast cells.4.In order to verify whether the effectors signal peptideassociated with secretion, with the help of pSUC2system, we havevalidated that the signal peptide of PXX93-2PR16-1related tosecretion.5.PXX93-2and PXX88-1effector gene were successfully knockedout and verified.This study not only provides new theoretical basis for revealingthe functions of effector genes in the rice blast fungus infection, can also understanding RNA silencing mechanism and the interactionbetween rice and Magnaporthe oryzae, help further to formulate thestrategy of rice blast fungus resistance.