Identification Of Transcription Factors MoAp1 And MoBzip10 Target Genes And Function Analysis In Magnaporthe Oryzae

Rice is the most important crop around the world,and it contributes to 30%of the caloric intake.M.oryzae is the causal agent of rice blast which lead to a threat to production worldwide,and the annual grain loss can feed about 60 million people.The prevention of M.oryzae mainly depends on the cultivation of resistant varieties and chemical control.The M.oryzae is easy to mutate,which makes the original resistant varieties lose their resistance,and the use of single chemical cause fungus become resistant to chemical drugs.Therefore,an effective control of rice blast is a difficult problem in food security.The molecular level study of M.oryzae can provide a new strategy for disease resistant and development of novel fungicides.In this paper,we focused on identification the target proteins of MoAp1 and MoBzip10,and analyzed the function of target proteins in development and pathogenicity,and the main results are showed as follows:Previous studies showed that the transcription factor(TF)MoApl as an oxidation transponder governs scavenges reactive oxygen species and is important for pathogenicity.Here,we identified a thioredoxin MpTRX2 through transcriptome of MoApl,and our result showed that the MoTRX2 promoter contains a MoAP1 binding site.We obtained MoTRX2 null mutant by gene knockout,the ΔMotrx2 mutants showed reduced growth in different medium,and had defect in sulfate assimilation.The asexual and sexual development of mutants were impaired,the pathogenicity of ΔMotrx2 mutants were significantly reduced on rice and the expansion of infected hyphae were limited in plant cell.This evidence suggested that MoTrx2 involves in growth,asexual and sexual development and pathogenicity.Reactive oxygen species(ROS)play a critical role in defense pathogen infection and are generally considered to be the first line of defense against pathogen infection.The burst of reactive oxygen species is very rapid,and the pathogen must respond quickly to the external stress.Pathogen contains variety strategies for rapid elimination ROS,including enzymes and non-enzymatic mechanisms,and many processes are regulated by transcription factors.The role of MoApl is scavenge ROS during infection.Compared with wild type,an enhanced amount of ROS was accumulation in the infected sites of MoTRX2 knockout mutants,and the expression levels of extracellular peroxidase and laccase genes were significantly decreased.We found that MoTrx2,as the target protein of MoApl,is involved in the removal of reactive oxygen species by regulating the expression of extracellular peroxidase and laccase,and involved in the pathogenic process.In addition,thioredoxins play a role in the intracellular ROS balance necessary for full virulence.The phosphorylation level of MAPK pathway related to infection was also significantly reduced in the mutant,which was one of the reasons for the decline of infection ability.Chromatin immunoprecipitation(ChIP)is an effective technique to analyze the interaction of protein and genome in vivo.ChIP coupled with high throughput sequencing plays an important role in research cellular transcription regulation and development network.Previous research showed that the MoBzip 10 is a pathogenicity related gene and involved in growth and asexual development.We used the ChIP-seq to analysis the target genes of MoBziplO.Ninety-five Peaks were identified by high through sequencing,and 55 Peak relation genes were found.One bingding site of MoBzip10 were predicted by MEME.In summary,thioredoxin MoTrx2 a target protein of MoApl,plays a critical role in the growth development.It participates the pathogenicity by regulating intracellular active oxygen balance,the elimination of active oxygen and phosphorylation level of MoMpsl.At the same time,the binding site of MoBzip10 was identified by ChIP-seq,and one predicted binding site was obtained.