Proteomic Analysis Of Wheat Induced By Puccinia Striiformis F. Sp Tritici At Telial Stage

Wheat stripe rust or yellow rust, caused by an obligate parasitic fungus Puccinia striiformis f. sp. tritici(Pst), is one of the important epidemic disease of wheat(Triticum aestivum)in China. Pst in China has shown high levels of genetic diversity and toxicity mutation. Research has shown that sexual reproduction of Pst can result in pathogenic mutation and produce new races. As the start of the sexual stage of wheat stripe rust, teliospore is an essential stage for completing Pst sexual reproduction. To analyze the differential proteins at telial stage of Pst and investigate the formation mechanism of teliospore, the proteomic changes of wheat leave infected by Pst at uredinial and telial stage were studied respectively, using two-dimensional electeophoresis( 2-DE). Differential proteins were analyzed by PDQuest software and the up-regulated protein spots were selected for Orbitrap analysis and database searching. The main results are as follows:1. Proteins were extracted from leaves infected with stripe rust CYR32 at telial stage, uredinial stage and control group using trichloroacetic acid(TCA)/phenol extraction, and then separated by using two-dimensional electeophoresis(2- DE). The results show that the protein spots were clear and independent using TCA/phenol extraction and IPG strip with 17 cm, pH 4.0-7.0.2. Using 2- DE and Orbitrap analysis, 28 and 50 up-regulated spots(relative expression more than 1.5 folds)were identified in Suwon11 leaves inoculated with stripe rust CYR32 at uredinial and telial stage, respectively. These proteins all belong to host plant. Comparison of the up-regulated protein in two stages found that they involved in similar metabolic pathways, such as glucose metabolism, anti-stress and cell regulation. Besides, there were 8 proteins up-regulated at both telial stage and uredinial stage. However, the result showed that 12 glucose metabolism-related proteins and 2 senescence related proteins were specifically expressed at telial stage of Pst.3. The results of qRT-PCR showed that some up-regulated protein genes at telial stage involved in important metabolic pathways exhibit the highest expression 6 days before teliospore generating. Besides, the expression of up-regulated proteins at transcriptional level are relatively consistent with that at protein level.Through the analysis of up-regulated proteins of wheat infected by Pst at both telial stage and uredinial stage, the results showed that the sporulation of Pst teliospores influences the expression of wheat proteins involved in glucose metabolism, anti-stress and plant senescence related metabolic pathways. Besides, compared with urediospore, the generation of teliospore may require more energy and it was assumed that the formation of teliospore may be associated with plant senescence.