The Role Of NbPIF1 In Harpin And SsCut-induced Plant Immunity

In the process of plants' development,they have to face a wide range of potential pathogens,including bacteria,viruses,fungi and menatodes.To resist the infection of pathogen,plant evolved a series of physiological and biochemical reaction to limit the pathogen invading,by the defense mechanism,such asstomatal closure,hypersensitive response.There are two kinds of innate immunity in plant:PAMPs triggered immunity and effector triggered immunity.plant elicitors induce immunity in plant,is a kind of PTI.Elicitors could induce plant defense responses:induce plant stomatal closure,hypersensitive response,the molecular mechanism remains to be further research.AT2G45120,a gene of Arabidopis thaliana,involved in regulating the signal transduction of guard cells,has high homology with NbPIF1 from the genebank of Nicotiana benthamiana(http://www.ncbi.nlm.nih.gov/).Bioinformatics analysis was carried out on the NbPIF1 that NbPIF1 is a C2H2-type Zinc finger protein any Zinc finger protein,ZnFC2H2.ZnFC2H2 contribute to development,stress resistance and other plant physiological and biochemical process,however,no research reports that relevant ZnFC2H2 protein about transcription factors involved in elicitor signal pathways and elicitor transduction of plant disease resistance reaction.In our experiments,use the model plant Nicotiana benthamiana,Virus induced gene silencing technology,can study gene function quickly and effectively.Through phenotype gene PDS,prove the efficient system gene silencing is useful.We show that silencing of NbPIF1 by virus-induced gene silencing attenuates stomatal closure induced by harpin from Xanthanmonas oryzae or SsCut from Sclerotinia sclerotiorum.And harpin and SsCut stimulate ROS accumulation both in PVX Nb and NbPIF1-silenced plants.NbPIF1-silenced attenuates harpin or SsCut-promoted ROS and NO production in stomata guard cells induced,and a reduction in harpin or SsCut-induced resistance against P.nicotianae.Taken together,these studies demonstrate that NbPIF1 gene,edcodes a C2H2-type zinc finger protein,is important in harpin or SsCut-mediated plant immunity and stomatal closure.Therefore the research silencing the ZnF C2H2 NbPIF1 gene by virus-induced gene silencing(VIGS),contributes to an understanding of C2H2 zinc finger protein transcription factors in the function of elicitor signal pathways,and is helpful to further understand the function of C2H2 zinc finger protein transcription factor.