Functional Dissection Of ?-aminobutyric Acid Receptor Aspartyl-tRNA Synthetase In Potato Induced Resistance Against P.infestans

?-Aminobutyric acid,or BABA,is a broad-spectrum chemical resistance inducer and belongs to nonprotein amino acids,which can induce resistance on many kinds of plants against various pathogens and stress with no damaging effects on environment.But it has the disadvantages of high cost and plants growth suppression.The mechanism of BABA induced resistance(BABA-IR)keeps unknown until a recent report said the receptor of BABA,a kind of aspartyl-tRNA synthetase,named as IBI1,had been found on Arabidopsis thaliana.After binding to BABA,AtIBI1 convert to a noncanonical defense function.Besides,the pathway of suppressing plant growth is differert from the one of enhancing defence,so it's possible to raise resistance without stress on growth.Our research find on potato the BABA receptor StAspRS,obtain over expression StAspRS potato lines,testify if the resistance is raised in transplant lines,and identify if the growth of transplant lines are suppressed,finally we use yeast two hybridization to find StAspRS interacting protein,in order to reveal mechanism futher.The main results are as follows:1.All genes with the function of aspartyl-tRNA synthetase on potato were found by bioinformation method.Afer comparing with At IBI1,the potato BABA receptor StAspRS were determined and cloned.Then expression pattern of StAspRS and three its homologous genes were analysised by qRT-PCR.The expression of StAspRS is higher after P.infestans inoculation but no change after BABA treatment.2.5 StAspRS over expression lines were obtained.Growth suppression occurs in relative 3 low over expression lines rather than 2 high ones.3.Late blight resistance on normal growth lines OE-5 and OE-6 were furhter evaluated.The lesion dimension?hypha growth rate and relative expression of marker genes of PTI,SA and JA signaling pathways showed that resistance of OE-5 and OE-6 increases.4.Bait vecror of intact StAspRS,N terminal fragment(StAspRS-N)and C terminal fragment(StAspRS-C)were constructed and use these baits to screen a library.No interaction has been found within StAspRS.StAspRS-N interact with StAspRS C terminal fragment from 131 to end and several other proteins.StAspRS-C interact with intact StAspRS and other proteins.Specific interaction demonstrates that StAspRS-C and StAspRS-N can interact with each other but intact StAspRS.Among other proteins only vacuolar protein-sorting-associated protein 11 homolog interacts with StAspRS-C.