| Wheat stripe rust,caused by a biotrophic obligate fungus Puccinia striiformis Westend.f.sp.tritici Eriks.,is one of the most devastating diseases in wheat production worldwide.Historically,it has been proved that breeding resistant varieties is one of the most effective and economical method to control stripe rust.However,new virulent races of stripe rust fungus emerge continuously by high virulence variability,which often causes resistance loss of wheat cultivars to stripe rust.Thus,it is important to understand molecular mechanism of wheat and stripe rust interaction to cultivate durable resistance wheat cultivars.In the interaction between wheat and stripe rust fungus with the typical "gene for gene" hypothesis,wheat resistance response is activated through the direct or indirect recognition of the pathogen avirulence(avr)gene product with corresponding resistance(R)gene product in wheat.Therefore,based on the information of plant resistance genes and pathogen avirulence genes,elucidating the interaction mechanism between avirulence gene and R gene is significantly important to use rationally the wheat resistance to stripe rust.Based on the project in the early completion of stripe rust of wheat whole genome sequencing,screen target genes;Construction of a candidate gene PVX expression vector,using Agrobacterium tumefaciens mediated virus expression system in tobacco were transiently expressed,through the analysis of its involvement in cell death induction or inhibition of BAX induced cell death,specific target gene toxic or nontoxic function.The main results are as follows:1 predict secretory protein of CYR32 by TargetP,SignalP3.0,TMHMM2.0 and through the filter with the transmembrane region of secreted proteins,the final selection of cysteine-rich(cysteine number>4)and encoded protein is less than 300amino acids,finally won 140 candidate genes;then design primer of the "ORF",through the PCR in the CYR32summer spore and wheat infected by168h samples were amplified and sequenced clones,obtaining 60target genes;2 construction of 60 target genes of the PVX carrier,will build a good purpose gene transferred into Agrobacterium feeling state,6 leaf period is good for the tobacco,by injection method in the tobacco transiently express,after injection of 5-10d observed symptoms.The experimental results show that the target gene can not directly induces necrosis nor inhibition caused by BAX programmed cell death,preliminary showed that60 target genes in tobacco with non-toxic function,but in the wheat in a specific function to be in wheat analysis and verification. |
