Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter gene...Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter genes,which function in conferring disease susceptibility(S)in rice plants.To engineer broadspectrum bacterial blight resistance,we used CRISPR/Cas9-mediated gene editing to disrupt the TALEbinding elements(EBEs)of two S genes,OsSWEETH and OsSWEET14,in rice cv.Kitaake,which harbors the recessive resistance allele of Xa25/OsSWEET13.The engineered rice line MS14K exhibited broadspectrum resistance to most Xoo strains with a few exceptions,suggesting that the compatible strains may contain new TALEs.We identified two PthXo2-like TALEs,Tal5LN18 and Tal7PX061,as major virulence factors in the compatible Xoo strains LN18 and PX061,respectively,and found that Xoo encodes at least five types of PthXo2-like effectors.Given that PthXo2/PthXo2.1 target OsSlVEETf3 for transcriptional activation,the genomes of 3000 rice varieties were analyzed for EBE variationsin the OsSWEET13 promoter,and 10Xa25-like haplotypes were identified.We found that Tal5LN18 and Tal7PX〇6i bind slightly different EBE sequences in the OsSWEET13 promoter to activate its expression.CRISPR/Cas9 technology was then used to generate InDels in the EBE of the OsSWEET13 promoter in MS14K to creat a new germplasm with three edited OsSWEET EBEs and broad-spectrum resistance against all Xoo strains tested.Collectively,our findings illustrate how to disarm TALE-S co-evolved loci to generate broad-spectrum resistance through the loss of effector-triggered susceptibility in plants.展开更多
Redundant techniques are widely adopted in vehicle management computer (VMC) to ensure that VMC has high reliability and safety. At the same time, it makes VMC have special characteristics, e.g., failure correlation...Redundant techniques are widely adopted in vehicle management computer (VMC) to ensure that VMC has high reliability and safety. At the same time, it makes VMC have special characteristics, e.g., failure correlation, event simultaneity, and failure self-recovery. Accordingly, the reliability and safety analysis to redundant VMC system (RVMCS) becomes more difficult. Aimed at the difficulties in RVMCS reliability modeling, this paper adopts generalized stochastic Petri nets to establish the reliability and safety models of RVMCS. Then this paper analyzes RVMCS oper- ating states and potential threats to flight control system. It is verified by simulation that the reli- ability of VMC is not the product of hardware reliability and software reliability, and the interactions between hardware and software faults can reduce the real reliability of VMC obviously. Furthermore, the failure undetected states and false alarming states inevitably exist in RVMCS due to the influences of limited fault monitoring coverage and false alarming probability of fault mon- itoring devices (FMD). RVMCS operating in some failure undetected states will produce fatal threats to the safety of flight control system. RVMCS operating in some false alarming states will reduce utility of RVMCS obviously. The results abstracted in this paper can guide reliable VMC and efficient FMD designs. The methods adopted in this paper can also be used to analyze other intelligent systems' reliability.展开更多
基金国家社科基金重大攻关项目"应对国际资源环境变化挑战与加快我国经济发展方式转变研究--基于政府规制视角"(批准号:09&ZD021)澳中理事会国际合作项目‘Australian-China trade and investment in a carbon constrained global economy:a research program’(批准号:ACC00008)+3 种基金广东省低碳发展专项资金资助项目"工业园废弃物综合利用体系建设与制度设计"(批准号:32412082)"乳源工业园区低碳发展目标路径和规划研究"(批准号:32412119)暨南大学科研培育与创新基金项目"区域旅游产业生态网络与城镇生态化发展的融合性研究"(批准号:11614111)
基金This research was supported by the National Key Research and Development Program of China(2016YFD0100601)the National Natural Science Foundation of China(31830072)the National Transgenic Major Program(2016ZX08001-002).
文摘Xanthomonas oryzae pv.oryzae(Xoo),the causal agent of bacterial blight of rice,employs the transcription activator-like effectors(TALEs)to induce the expression of the OsSWEET family of putative sugar transporter genes,which function in conferring disease susceptibility(S)in rice plants.To engineer broadspectrum bacterial blight resistance,we used CRISPR/Cas9-mediated gene editing to disrupt the TALEbinding elements(EBEs)of two S genes,OsSWEETH and OsSWEET14,in rice cv.Kitaake,which harbors the recessive resistance allele of Xa25/OsSWEET13.The engineered rice line MS14K exhibited broadspectrum resistance to most Xoo strains with a few exceptions,suggesting that the compatible strains may contain new TALEs.We identified two PthXo2-like TALEs,Tal5LN18 and Tal7PX061,as major virulence factors in the compatible Xoo strains LN18 and PX061,respectively,and found that Xoo encodes at least five types of PthXo2-like effectors.Given that PthXo2/PthXo2.1 target OsSlVEETf3 for transcriptional activation,the genomes of 3000 rice varieties were analyzed for EBE variationsin the OsSWEET13 promoter,and 10Xa25-like haplotypes were identified.We found that Tal5LN18 and Tal7PX〇6i bind slightly different EBE sequences in the OsSWEET13 promoter to activate its expression.CRISPR/Cas9 technology was then used to generate InDels in the EBE of the OsSWEET13 promoter in MS14K to creat a new germplasm with three edited OsSWEET EBEs and broad-spectrum resistance against all Xoo strains tested.Collectively,our findings illustrate how to disarm TALE-S co-evolved loci to generate broad-spectrum resistance through the loss of effector-triggered susceptibility in plants.
基金Supported by the National Natural Science Foundation of China, Grant No. 30470123, the Natural Science Foundation of Yunnan Province, Grant No. 2001C0008R, the Research Fund for Returned Overseas Chinese Scholars, Grant No. 20010713093959, and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry, Grant No. 2001-498.
基金financed by the National Natural Science Foundation of China (No.61004022)111 Project of China Education Department
文摘Redundant techniques are widely adopted in vehicle management computer (VMC) to ensure that VMC has high reliability and safety. At the same time, it makes VMC have special characteristics, e.g., failure correlation, event simultaneity, and failure self-recovery. Accordingly, the reliability and safety analysis to redundant VMC system (RVMCS) becomes more difficult. Aimed at the difficulties in RVMCS reliability modeling, this paper adopts generalized stochastic Petri nets to establish the reliability and safety models of RVMCS. Then this paper analyzes RVMCS oper- ating states and potential threats to flight control system. It is verified by simulation that the reli- ability of VMC is not the product of hardware reliability and software reliability, and the interactions between hardware and software faults can reduce the real reliability of VMC obviously. Furthermore, the failure undetected states and false alarming states inevitably exist in RVMCS due to the influences of limited fault monitoring coverage and false alarming probability of fault mon- itoring devices (FMD). RVMCS operating in some failure undetected states will produce fatal threats to the safety of flight control system. RVMCS operating in some false alarming states will reduce utility of RVMCS obviously. The results abstracted in this paper can guide reliable VMC and efficient FMD designs. The methods adopted in this paper can also be used to analyze other intelligent systems' reliability.