The Roles Of Plant RpsYu Gene In Disease Resistance And Tolerance To Abiotic Stresses

Plants have a variety of physiological and biochemical mechanisms to resist pathogenic microorganisms in the growth environment.In order to successfully infect plants,pathogenic microorganisms evolved effectors to suppress plant disease resistance,and plants evolved disease resistance(R)genes to monitor and recognize these effectors to stimulate strong disease resistance responses.Therefore,cloning the crop R gene and understanding its disease resistance mechanism is the focus of research on disease resistant breeding of today’s crops.A hybrid group of soybean root rot resistant and susceptible varieties was constructed in previous work from our group,and the C2H2 zinc finger protein transcription factor RpsYu gene,which was obtained by map-based cloning and fine mapping,is a novel R gene in soybean.This paper investigates the function of RpsYu and its homologous protein AtRpsYu in Arabidopsis thaliana in plant disease resistance,abiotic adversity stress and growth development.The results of the study are as follows:1.RpsYu positively regulates soybean resistance to Phytophthora sojae and Pseudomonas syringae,and the transcript levels of the pathogenesis-related genes PR1-08 and PR1-15 were significantly higher in soybean RpsYu overexpressing plants than in non-transgenic control plants.In addition,RpsYu affects physiological index such as leaf length and width,plant height,and chlorophyll content during soybean response to disease.2.RpsYu overexpressing Arabidopsis thaliana plants differed significantly from Col-0wild-type control phenotypes,with central leaf curls and increased epidermal hairs in RpsYu overexpressing plants.RpsYu is modulating Arabidopsis thaliana resistance to abiotic stresses,including increased drought tolerance and high salt tolerance.RpsYu overexpressing Arabidopsis thaliana plants were found to have significantly higher transcript levels of salt stress response genes AtSOS1,AtSOS2 and drought tolerance genes AtRD29 A than wild-type control Arabidopsis thaliana by Real-time PCR,consistent with its salt tolerance and drought resistance phenotype.3.RpsYu positively regulates the resistance of Arabidopsis thaliana to Pseudomonas syringae pv.tomato DC3000.RpsYu overexpressing Arabidopsis thaliana plants inoculated with Pst.DC3000 with milder symptom and significantly fewer pathogenic bacteria in the leaves than Col-0 wild-type plants.The Arabidopsis RpsYu over-expressing plant pathogenesis-related genes AtPR1 and AtPR2 were detected to be up-regulated more rapidly and have higher transcription levels than Col-0 wild-type plants.4.The organ-specific expression analysis of Arabidopsis thaliana showed that the AtRpsYu gene was expressed highest in leaves.Compared with Col-0 wild type plants,Arabidopsis atrpsyu mutant plants exhibited plant retardation,with smaller leaves and shorter roots.The atrpsyu mutant plants were more sensitive to abiotic stress,with growth inhibition and lower survival rate under high salt and drought stress.In addition,the transcript levels of the salt stress response-related gene AtSOS1 and the drought tolerance-related gene AtRD29 A were significantly lower in atrpsyu mutant plants than in Col-0 wild-type plants,indicating that AtRpsYu is positively regulating plant stress resistance.5.It was observed that atrpsyu mutant plants were more susceptible and had longer lesion diameters than Col-0 wild-type plants after inoculation with Botrytis cinerea.The upward trend of resistance-related gene PDF1.2 in atrpsyu mutant plants was not as pronounced as in Col-0 wild-type plants,and the expression of the marker gene Actin was higher,suggesting that atrpsyu is positively regulating resistance to Botrytis cinerea in Arabidopsis.