Bacterial wilt disease caused by several Ralstonia species is one of the most destructive diseases in Solanaceae crops.Only a few functional resistance genes against bacterial wilt have been cloned to date.Here,we sho...Bacterial wilt disease caused by several Ralstonia species is one of the most destructive diseases in Solanaceae crops.Only a few functional resistance genes against bacterial wilt have been cloned to date.Here,we showthat the broadly conserved typeⅢsecreted effector RipY is recognized by the Nicotiana benthamiana immune system,leading to cell death induction,induction of defense-related gene expression,and restriction of bacterial pathogen growth.Using a multiplexed virus-induced gene-silencing-based N.benthamiana nucleotide-binding and leucine-rich repeat receptor(NbNLR)library,we identified a coiled-coil(CC)nucleotide-binding and leucine-rich repeat receptor(CNL)required for recognition of RipY,which we named RESISTANCE TO RALSTONIA SOLANACEARUM RIPY(RRS-Y).Genetic complementation assays in RRS-Y-silenced plants and stable rrs-y knockout mutants demonstrated that RRS-Y is sufficient to activate RipY-induced cell death andRipY-induced immunity to Ralstonia pseudosolanacearum.RRS-Y function is dependent on the phosphate-binding loop motif of the nucleotide-binding domain but independent of the characterized signaling components ENHANCED DISEASE SUSCEPTIBILITY 1,ACTIVATED DISEASE RESISTANCE 1,and N REQUIREMENT GENE 1 and the NLR helpers NB-LRR REQUIRED FOR HR-ASSOCIATED CELL DEATH-2,-3,and-4 in N.benthamiana.We further show that RRS-Y localization at the plasma membrane is mediated by two cysteine residues in the CC domain and is required for RipY recognition.RRSY also broadly recognizes RipY homologs across Ralstonia species.Lastly,we show that the C-terminal region of RipY is indispensable for RRS-Y activation.Together,our findings provide an additional effector/receptor pair system to deepen our understanding of CNL activation in plants.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Korean Ministry of Education(Global PhD Fellowship Program Project 500–20190213)by the Ministry of Sciences and ICT(Projects 2018R1A5A1023599,2020R1A2C1101419).
文摘Bacterial wilt disease caused by several Ralstonia species is one of the most destructive diseases in Solanaceae crops.Only a few functional resistance genes against bacterial wilt have been cloned to date.Here,we showthat the broadly conserved typeⅢsecreted effector RipY is recognized by the Nicotiana benthamiana immune system,leading to cell death induction,induction of defense-related gene expression,and restriction of bacterial pathogen growth.Using a multiplexed virus-induced gene-silencing-based N.benthamiana nucleotide-binding and leucine-rich repeat receptor(NbNLR)library,we identified a coiled-coil(CC)nucleotide-binding and leucine-rich repeat receptor(CNL)required for recognition of RipY,which we named RESISTANCE TO RALSTONIA SOLANACEARUM RIPY(RRS-Y).Genetic complementation assays in RRS-Y-silenced plants and stable rrs-y knockout mutants demonstrated that RRS-Y is sufficient to activate RipY-induced cell death andRipY-induced immunity to Ralstonia pseudosolanacearum.RRS-Y function is dependent on the phosphate-binding loop motif of the nucleotide-binding domain but independent of the characterized signaling components ENHANCED DISEASE SUSCEPTIBILITY 1,ACTIVATED DISEASE RESISTANCE 1,and N REQUIREMENT GENE 1 and the NLR helpers NB-LRR REQUIRED FOR HR-ASSOCIATED CELL DEATH-2,-3,and-4 in N.benthamiana.We further show that RRS-Y localization at the plasma membrane is mediated by two cysteine residues in the CC domain and is required for RipY recognition.RRSY also broadly recognizes RipY homologs across Ralstonia species.Lastly,we show that the C-terminal region of RipY is indispensable for RRS-Y activation.Together,our findings provide an additional effector/receptor pair system to deepen our understanding of CNL activation in plants.
