Crop yield is at increasing risk due to water scarcity and climate change.Agrochemicals can activate hor-mone receptors to regulate transpiration and modulate transcription and address water deficits.Structure-guided ...Crop yield is at increasing risk due to water scarcity and climate change.Agrochemicals can activate hor-mone receptors to regulate transpiration and modulate transcription and address water deficits.Structure-guided optimization of multiple abscisic acid(ABA)receptor-agonist interactions is necessary to activate theentirePYRABACTINRESISTANCE1(PYR1)/PYR1-LIKE(PYL)/REGULATORYCOMPONENTSOFABA RECEPTORS(RCAR)receptor family.The new agonist iCB,produced through scaffold-merging led by X-ray structure,activates subfamilies Il and Ill at low-nM concentrations and subfamily I receptors at higher-nM concentrations.Structural analysis of opabactin and icB ternary complexes reveals selectivity-determining residues,making the PYL1/PYL4/PYL8 subfamilies sensitive to specific agonists and highlighting the differential sensitivity of receptor subfamilies to agonists across plant species.icB may activate mosteudicots'PYL8-like receptors,incontrastto opabactin,dueto limited steric constraints.This enables iCB to activate PYL8-like receptors with a bulkier Leu residue in the 3'tunnel,such as AtPYL8,SIPYL8,and VviPYL8.In contrast,opabactin activation is limited to receptors with Val at this position,for example,TaPYL8.Therefore,iCBextends its action to moreABAreceptors than CB,iSBo9,andopabactin,exhibits higher affinity than ABA for dimeric receptors,and can protect tomato plants against drought.In addition to regulating stomatal conductance and lowering water consumption,icB protects photosystem Il and improves photosynthesis following prolonged water deficit.Moreover,icB induces an ABA-like tran-scriptional response,upregulates the osmolyte synthesis,and can be hyperpotentiated when combined with the expression of a customized receptor.Our results provide structural insightsfor optimizing agonist designand aiding plants in managing water deficits.展开更多
Fleshy fruit ripening is typically regulated by ethylene in climacteric fruits and abscisic acid(ABA)in non-climacteric fruits.Common fig(Ficus carica)shows a dual-ripening mechanism,which is not fully understood.Here...Fleshy fruit ripening is typically regulated by ethylene in climacteric fruits and abscisic acid(ABA)in non-climacteric fruits.Common fig(Ficus carica)shows a dual-ripening mechanism,which is not fully understood.Here,we detected separate peaks of ethylene and ABA in fig fruits at the onset-and onripening stages,in conjunction with a sharp rise in glucose and fructose contents.In a newly-designed split-fruit system,exogenous ethylene failed to rescue fluridone-inhibited fruit ripening,whereas exogenous ABA rescued 2-amino-ethoxy-vinyl glycine(AVG)-inhibited fruit ripening.Transcriptome analysis revealed changes in the expression of genes key to both ABA and ethylene biosynthesis and perception during fig fruit ripening.At the degreening stage,downregulation of FcACO2 or FcPYL8 retarded ripening,but downregulation of FcETR1/2 did not;unexpectedly,downregulation of FcAAO3 promoted ripening,but it inhibited ripening only before the de-greening stage.Furthermore,we detected an increase in ethylene emissions in the FcAAO3-RNAi ripening fruit and a decrease in ABA levels in the FcACO2-RNAi unripening fruit.Importantly,FcPYL8 can bind to ABA,suggesting that it functions as an ABA receptor.Our findings support the hypothesis that ethylene regulates the fig fruit ripening in an ABA-dependent manner.We propose a model for the role of the ABA-ethylene interaction in climacteric/non-climacteric processes.展开更多
基金supported by Agencia Estatal de Investigacion of the Spanish Ministry of Science and Innovation with grant numbers PID2020-119805RB-I00 and PID2023-1531080B-I00(A.A.)grant numbers PID2020-113100RB-I00 and PID2023-1473220OB-I00(P.L.R.)+7 种基金funded by MCIN/AEl/10.13039/501100011033 and the European Regional Development Fund(ERDF)("A way of making Europe")support from Agencia Estatal de Investigacion of the Spanish Ministry of Science and Innovation with grant number TED2021-129867B-C21(P.L.R.)grant number TED2021-132202B-I00(A.A.)funded by MCIU/AEI/10.13039/501100011033 and by the European Union NextGenerationEU/PRTR.J.C.Esupported by Agencia Estatal de Investigacion(CPP2021-009090,PID2022-136848NB-100),the Xunta de Galicia(ED431C 2022/21,ED431F 2020/05)Centro de investigacion do Sistema universitario de Galicia/accreditation 2023-2027,ED431G 2023/03the European Union(European Regional Development Fund--ERDF)supported by the Estonian Research Council(grant numberPRG 1620).
文摘Crop yield is at increasing risk due to water scarcity and climate change.Agrochemicals can activate hor-mone receptors to regulate transpiration and modulate transcription and address water deficits.Structure-guided optimization of multiple abscisic acid(ABA)receptor-agonist interactions is necessary to activate theentirePYRABACTINRESISTANCE1(PYR1)/PYR1-LIKE(PYL)/REGULATORYCOMPONENTSOFABA RECEPTORS(RCAR)receptor family.The new agonist iCB,produced through scaffold-merging led by X-ray structure,activates subfamilies Il and Ill at low-nM concentrations and subfamily I receptors at higher-nM concentrations.Structural analysis of opabactin and icB ternary complexes reveals selectivity-determining residues,making the PYL1/PYL4/PYL8 subfamilies sensitive to specific agonists and highlighting the differential sensitivity of receptor subfamilies to agonists across plant species.icB may activate mosteudicots'PYL8-like receptors,incontrastto opabactin,dueto limited steric constraints.This enables iCB to activate PYL8-like receptors with a bulkier Leu residue in the 3'tunnel,such as AtPYL8,SIPYL8,and VviPYL8.In contrast,opabactin activation is limited to receptors with Val at this position,for example,TaPYL8.Therefore,iCBextends its action to moreABAreceptors than CB,iSBo9,andopabactin,exhibits higher affinity than ABA for dimeric receptors,and can protect tomato plants against drought.In addition to regulating stomatal conductance and lowering water consumption,icB protects photosystem Il and improves photosynthesis following prolonged water deficit.Moreover,icB induces an ABA-like tran-scriptional response,upregulates the osmolyte synthesis,and can be hyperpotentiated when combined with the expression of a customized receptor.Our results provide structural insightsfor optimizing agonist designand aiding plants in managing water deficits.
基金supported by the National Natural Science Foundation of China(32030100 and 31672125)the Beijing Natural Science Foundation(6171001)Sichuan Lomon Biotechnology Co.Ltd。
文摘Fleshy fruit ripening is typically regulated by ethylene in climacteric fruits and abscisic acid(ABA)in non-climacteric fruits.Common fig(Ficus carica)shows a dual-ripening mechanism,which is not fully understood.Here,we detected separate peaks of ethylene and ABA in fig fruits at the onset-and onripening stages,in conjunction with a sharp rise in glucose and fructose contents.In a newly-designed split-fruit system,exogenous ethylene failed to rescue fluridone-inhibited fruit ripening,whereas exogenous ABA rescued 2-amino-ethoxy-vinyl glycine(AVG)-inhibited fruit ripening.Transcriptome analysis revealed changes in the expression of genes key to both ABA and ethylene biosynthesis and perception during fig fruit ripening.At the degreening stage,downregulation of FcACO2 or FcPYL8 retarded ripening,but downregulation of FcETR1/2 did not;unexpectedly,downregulation of FcAAO3 promoted ripening,but it inhibited ripening only before the de-greening stage.Furthermore,we detected an increase in ethylene emissions in the FcAAO3-RNAi ripening fruit and a decrease in ABA levels in the FcACO2-RNAi unripening fruit.Importantly,FcPYL8 can bind to ABA,suggesting that it functions as an ABA receptor.Our findings support the hypothesis that ethylene regulates the fig fruit ripening in an ABA-dependent manner.We propose a model for the role of the ABA-ethylene interaction in climacteric/non-climacteric processes.
