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
Plant stomata close rapidly in response to a rise in the plant hormone abscisic acid(ABA)or salicylic acid(SA)and after recognition of pathogenassociated molecular patterns(PAMPs).Stomatal closure is the result of vac...Plant stomata close rapidly in response to a rise in the plant hormone abscisic acid(ABA)or salicylic acid(SA)and after recognition of pathogenassociated molecular patterns(PAMPs).Stomatal closure is the result of vacuolar convolution,ion efflux,and changes in turgor pressure in guard cells.Phytopathogenic bacteria secrete typeⅢeffectors(T3Es)that interfere with plant defense mechanisms,causing severe plant disease symptoms.Here,we show that the virulence and infection of Xanthomonas oryzae pv.oryzicola(Xoc),which is the causal agent of rice bacterial leaf streak disease,drastically increased in transgenic rice(Oryza sativa L.)plants overexpressing the Xoc T3E gene Xop AP,which encodes a protein annotated as a lipase.We discovered that Xop AP binds to phosphatidylinositol 3,5-bisphosphate(Ptd Ins(3,5)P_(2)),a memb rane phospholipid that functions in p H control in lysosomes,membrane dynamics,and protein trafficking.Xop AP inhibited the acidification of vacuoles by competing with vacuolar H^(+)-pyrophosphatase(V-PPase)for binding to Ptd Ins(3,5)P_(2),leading to stomatal opening.Transgenic rice overexpressing Xop AP also showed inhibition of stomatal closure when challenged by Xoc infection and treatment with the PAMP flg22.Moreover,Xop AP suppressed flg22-induced gene expression,reactive oxygen species burst and callose deposition in host plants,demonstrating that Xop AP subverts PAMP-triggered immunity during Xoc infection.Taken together,these findings demonstrate that Xop AP overcomes stomatal immunity in plants by binding to lipids.展开更多
To protect themselves from infectious diseases,plants have deployed a two-tiered surveillance system to recognize invading pathogens(Fu and Dong,2013).In the first layer of the immune system,plants evolved extracellul...To protect themselves from infectious diseases,plants have deployed a two-tiered surveillance system to recognize invading pathogens(Fu and Dong,2013).In the first layer of the immune system,plants evolved extracellular patter n recognition receptors to detect con served pathoge n-associated molecular patterns(PAM Ps)and activate PAMP-triggered immunity(PTI)(Boiler and Felix,2009).展开更多
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 Shanghai Agriculture Applied Technology Development Program,China(2020-02-08-00-08-F01462)the National Natural Science Foundation of China(31830072,32102147)。
文摘Plant stomata close rapidly in response to a rise in the plant hormone abscisic acid(ABA)or salicylic acid(SA)and after recognition of pathogenassociated molecular patterns(PAMPs).Stomatal closure is the result of vacuolar convolution,ion efflux,and changes in turgor pressure in guard cells.Phytopathogenic bacteria secrete typeⅢeffectors(T3Es)that interfere with plant defense mechanisms,causing severe plant disease symptoms.Here,we show that the virulence and infection of Xanthomonas oryzae pv.oryzicola(Xoc),which is the causal agent of rice bacterial leaf streak disease,drastically increased in transgenic rice(Oryza sativa L.)plants overexpressing the Xoc T3E gene Xop AP,which encodes a protein annotated as a lipase.We discovered that Xop AP binds to phosphatidylinositol 3,5-bisphosphate(Ptd Ins(3,5)P_(2)),a memb rane phospholipid that functions in p H control in lysosomes,membrane dynamics,and protein trafficking.Xop AP inhibited the acidification of vacuoles by competing with vacuolar H^(+)-pyrophosphatase(V-PPase)for binding to Ptd Ins(3,5)P_(2),leading to stomatal opening.Transgenic rice overexpressing Xop AP also showed inhibition of stomatal closure when challenged by Xoc infection and treatment with the PAMP flg22.Moreover,Xop AP suppressed flg22-induced gene expression,reactive oxygen species burst and callose deposition in host plants,demonstrating that Xop AP subverts PAMP-triggered immunity during Xoc infection.Taken together,these findings demonstrate that Xop AP overcomes stomatal immunity in plants by binding to lipids.
基金supported by the grant from National Science Foundation(IOS-1758994)to Z.Q.F.by grants from Jiangsu University High-Level Talent Funding(20JDG34)National Natural Science Foundation of China(32000201)to J.C.
文摘To protect themselves from infectious diseases,plants have deployed a two-tiered surveillance system to recognize invading pathogens(Fu and Dong,2013).In the first layer of the immune system,plants evolved extracellular patter n recognition receptors to detect con served pathoge n-associated molecular patterns(PAM Ps)and activate PAMP-triggered immunity(PTI)(Boiler and Felix,2009).
