Functional Characterization Of Cell Death-related Genes TaVPE3 During The Interaction Of Wheat And Stripe Rust Fungus

Wheat stripe rust caused by Puccinia striiformis f.sp.tritici(Pst),which is a biotrophic and completely dependent on living host cells for reproduction.The use of resistant varieties is the most effective measures to control wheat stripe rust,however the frequent variation often results in the loss of wheat resistance to Pst,and causes the huge loss of wheat production,therefore,research on the resistance mechanism,and developing the new strategies of the control of wheat stripe rust will be of great significance.Previous research found that wheat produce hypersensitive reaction(HR)to prevent the expansion of the Pst and achieve the goal of disease resistance.Some reports indicated that Vacuolar processing enzyme has similar activity of casapase,which regulate the programmed cell death(PCD)in animal cells apoptosis by catalytic activation.Hence,in our study,we studied the function of Ta VPE3 during wheat and Pst,which will be helpful for the understanding the molecular mechanism of wheat resistance to stripe rust.The main results were as follows:We cloned a wheat gene Ta VPE3,named Ta VPE3.The bioinformatics analysis indicated that Ta VPE3 contains protein signal peptide sequence.Evolutionary tree analysis showed that Ta VPE3 is closely relative to barley VPE3 and belongs to the nutritional VPE family.Ta VPE3 is a class of cysteine protease enzyme,in vitro experimental results showed that the Ta VPE3 protein has typical animal cysteine protease Caspase1 enzyme activity.subcellular localization showed that Ta VPE3 expressed in the nucleus and the cell membrane.The glyceraldehyde-3-phosphate dehydrogenase(GAPDH)is a potential target of Ta VPE3 by screening the yeast two-hybrid libraries.Further studies conformed that there was an interaction between Ta GAPDH and Ta VPE3 using the bimolecular fluorescence complementation and pull down.The knocking down of Ta GAPDH increased the resistance of wheat to Pst.