The transcription factor WRKY70 was previously reported to be a common component in salicylic acid （SA） and jasmonate （JA） mediated signal pathways in Arabidopsis. Here, we present that the inactivation of the WRK...The transcription factor WRKY70 was previously reported to be a common component in salicylic acid （SA） and jasmonate （JA） mediated signal pathways in Arabidopsis. Here, we present that the inactivation of the WRKY70 gene in wrky70-1 mutant does not alter the responses of both JA and SA, and that wrky70 mutation is unable to restore the coil mutant in JA responses. However, overexpression of WRKY70 reduces JA responses such as expression of JA-induced genes and JA-inhibitory root growth, and activates expression of SA-inducible PR1. These data indicate that the WRKY70 is important but not indispensable for JA and SA signaling, and that other regulators may display the redundant role with WRKY70 in modulation of JA and SA responses in Arabidopsis. Furthermore, we showed that JA inhibits expression of WRKY70 and PR1 by both COi1-dependent and COi1-independent pathways.展开更多
ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the...ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the plant hypoxia response by interacting with WRKY70,influencing its nucleocytoplasmic shuttling in Arabidopsis thaliana.Furthermore,we demonstrate the direct binding of WRKY70 to the ACBP4 promoter,resulting in its upregulation and suggesting a positive feedback loop.Additionally,we pinpointed a phosphorylation site at Ser638 of ACBP4,which enhances submergence tolerance,potentially by facilitating WRKY70's nuclear shuttling.Surprisingly,a natural variation in this phosphorylation site of ACBP4 allowed A.thaliana to adapt to humid conditions during its historical demographic expansion.We further observed that both phosphorylated ACBP4 and oleoyl-Co A can impede the interaction between ACBP4 and WRKY70,thus promoting WRKY70's nuclear translocation.Finally,we found that the overexpression of orthologous Bna C5.ACBP4and Bna A7.WRKY70 in Brassica napus increases submergence tolerance,indicating their functional similarity across genera.In summary,our research not only sheds light on the functional significance of the ACBP4 gene in hypoxia response,but also underscores its potential utility in breeding flooding-tolerant oilseed rape varieties.展开更多
Submergence stress tolerance is a complex trait governed by multiple loci.Because of its wide distribution across arid and humid regions,Arabidopsis thaliana offers an opportunity to explore the genetic components and...Submergence stress tolerance is a complex trait governed by multiple loci.Because of its wide distribution across arid and humid regions,Arabidopsis thaliana offers an opportunity to explore the genetic components and their action mechanisms underlying plant adaptation to submergence stress.In this study,using map-based cloning we identified WRKY22 that activates RAP2.12,a locus previously identified to contribute to the submergence stress response,to regulate plant humid adaptation possibly through ethylene signal transduction in Arabidopsis.WRKY22 expression is inhibited by ARABIDOPSIS RESPONSE REGULATORs(ARRs)but activated by the WRKY70 transcription factor.In accessions from humid environments,a two-nucleotide deletion in the WRKY22 promoter region prevents binding of phosphorylated ARRs,thereby maintaining its high expression.Loss of the ARR-binding element in the WRKY22 promoter underwent strong positive selection during colonization of A.thaliana in the humid Yangtze River basin.However,the WRKY70-binding motif in the WRKY22 promoter shows no variation between accessions from humid and arid regions.These findings together establish a novel signaling axis wherein WRKY22 plays a key role in regulating the adaptive response that enables A.thaliana to colonize contrasting habitats.Notably,we further showed functional conservation of this locus in Brassica napus,suggesting that modulating this axis might be useful in the breeding of flood-tolerant crop varieties.展开更多
Ultraviolet-B(UV-B)radiation,a pervasive light stimulus,profoundly influences plant hypocotyl growth through intricate signaling pathways.Although the core UV-B signaling components have been identified,the precise re...Ultraviolet-B(UV-B)radiation,a pervasive light stimulus,profoundly influences plant hypocotyl growth through intricate signaling pathways.Although the core UV-B signaling components have been identified,the precise regulatory mechanisms remain elusive.Here,we identify prefoldin 3(PFD3),anαsubunit of the PFD complex,as a novel negative regulator of UV-B-induced hypocotyl growth inhibition in Arabidopsis thaliana.Upon UV-B exposure,PFD3 accumulates and promotes the turnover of WRKY DNA-BINDING PROTEIN 70(WRKY70)and FAR-RED ELONGATED HYPOCOTYL 3(FHY3),thereby attenuating their transcriptional activities toward ELONGATED HYPOCOTYL 5(HY5)/PACLOBUTRAZOL RESISTANCE1(PRE1)and CONSTITUTIVE PHOTOMORPHOGENIC 1(COP1),respectively.These findings delineate two regulatory modules-PFD3-WRKY70-HY5/PRE1 and PFD3-FHY3-COP1-that fine-tune UV-B-mediated inhibition of hypocotyl elongation in a UV RESISTANCE LOCUS 8-dependent manner.Furthermore,we identify amino acid variations in FHY3 from the high-altitude Xizang-0 ecotype of A.thaliana that confer resistance to PFD3mediated suppression.This genetic adaptation sustains COP1 activation and results in shortened hypocotyls under UV-B radiation in this alpine ecotype.Collectively,our results suggest that allelic variation within these modules enhances adaptation to high-intense UV-B habitats,highlighting the evolutionary significance of these regulatory networks in plant environmental acclimation.展开更多
基金the National Natural Science Foundation of China (30630044,30671121,30770195 and 30771147).
文摘The transcription factor WRKY70 was previously reported to be a common component in salicylic acid （SA） and jasmonate （JA） mediated signal pathways in Arabidopsis. Here, we present that the inactivation of the WRKY70 gene in wrky70-1 mutant does not alter the responses of both JA and SA, and that wrky70 mutation is unable to restore the coil mutant in JA responses. However, overexpression of WRKY70 reduces JA responses such as expression of JA-induced genes and JA-inhibitory root growth, and activates expression of SA-inducible PR1. These data indicate that the WRKY70 is important but not indispensable for JA and SA signaling, and that other regulators may display the redundant role with WRKY70 in modulation of JA and SA responses in Arabidopsis. Furthermore, we showed that JA inhibits expression of WRKY70 and PR1 by both COi1-dependent and COi1-independent pathways.
基金the Natural Science Foundation of China(No.32270302 and No.32030006)the Fundamental Research Funds for the Central Universities(SCU2022D003)。
文摘ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the plant hypoxia response by interacting with WRKY70,influencing its nucleocytoplasmic shuttling in Arabidopsis thaliana.Furthermore,we demonstrate the direct binding of WRKY70 to the ACBP4 promoter,resulting in its upregulation and suggesting a positive feedback loop.Additionally,we pinpointed a phosphorylation site at Ser638 of ACBP4,which enhances submergence tolerance,potentially by facilitating WRKY70's nuclear shuttling.Surprisingly,a natural variation in this phosphorylation site of ACBP4 allowed A.thaliana to adapt to humid conditions during its historical demographic expansion.We further observed that both phosphorylated ACBP4 and oleoyl-Co A can impede the interaction between ACBP4 and WRKY70,thus promoting WRKY70's nuclear translocation.Finally,we found that the overexpression of orthologous Bna C5.ACBP4and Bna A7.WRKY70 in Brassica napus increases submergence tolerance,indicating their functional similarity across genera.In summary,our research not only sheds light on the functional significance of the ACBP4 gene in hypoxia response,but also underscores its potential utility in breeding flooding-tolerant oilseed rape varieties.
基金supported by the Natural Science Foundation of China(No.32270302 and No.32030006)the Fundamental Research Funds for the Central Universities(2020SCUNL207 and SCU2022D003)+1 种基金Natural Science Foundation of Sichuan Province(2024NSFSC0340 and 25QNJJ4460)Sichuan Forage Innovation Team Program(SCCXTD-2024-16).
文摘Submergence stress tolerance is a complex trait governed by multiple loci.Because of its wide distribution across arid and humid regions,Arabidopsis thaliana offers an opportunity to explore the genetic components and their action mechanisms underlying plant adaptation to submergence stress.In this study,using map-based cloning we identified WRKY22 that activates RAP2.12,a locus previously identified to contribute to the submergence stress response,to regulate plant humid adaptation possibly through ethylene signal transduction in Arabidopsis.WRKY22 expression is inhibited by ARABIDOPSIS RESPONSE REGULATORs(ARRs)but activated by the WRKY70 transcription factor.In accessions from humid environments,a two-nucleotide deletion in the WRKY22 promoter region prevents binding of phosphorylated ARRs,thereby maintaining its high expression.Loss of the ARR-binding element in the WRKY22 promoter underwent strong positive selection during colonization of A.thaliana in the humid Yangtze River basin.However,the WRKY70-binding motif in the WRKY22 promoter shows no variation between accessions from humid and arid regions.These findings together establish a novel signaling axis wherein WRKY22 plays a key role in regulating the adaptive response that enables A.thaliana to colonize contrasting habitats.Notably,we further showed functional conservation of this locus in Brassica napus,suggesting that modulating this axis might be useful in the breeding of flood-tolerant crop varieties.
基金supported by the Natural Science Foundation of China(nos.32030006,31870244,and 32270302)the Natural Science Foundation of Sichuan Province(2024NSFSC0340 and 2025ZNSFSC1013)+1 种基金the Sichuan Forage Innovation Team Program(SCCXTD-2024-16)the Fundamental Research Funds for the Central Universities(SCU2022D003).
文摘Ultraviolet-B(UV-B)radiation,a pervasive light stimulus,profoundly influences plant hypocotyl growth through intricate signaling pathways.Although the core UV-B signaling components have been identified,the precise regulatory mechanisms remain elusive.Here,we identify prefoldin 3(PFD3),anαsubunit of the PFD complex,as a novel negative regulator of UV-B-induced hypocotyl growth inhibition in Arabidopsis thaliana.Upon UV-B exposure,PFD3 accumulates and promotes the turnover of WRKY DNA-BINDING PROTEIN 70(WRKY70)and FAR-RED ELONGATED HYPOCOTYL 3(FHY3),thereby attenuating their transcriptional activities toward ELONGATED HYPOCOTYL 5(HY5)/PACLOBUTRAZOL RESISTANCE1(PRE1)and CONSTITUTIVE PHOTOMORPHOGENIC 1(COP1),respectively.These findings delineate two regulatory modules-PFD3-WRKY70-HY5/PRE1 and PFD3-FHY3-COP1-that fine-tune UV-B-mediated inhibition of hypocotyl elongation in a UV RESISTANCE LOCUS 8-dependent manner.Furthermore,we identify amino acid variations in FHY3 from the high-altitude Xizang-0 ecotype of A.thaliana that confer resistance to PFD3mediated suppression.This genetic adaptation sustains COP1 activation and results in shortened hypocotyls under UV-B radiation in this alpine ecotype.Collectively,our results suggest that allelic variation within these modules enhances adaptation to high-intense UV-B habitats,highlighting the evolutionary significance of these regulatory networks in plant environmental acclimation.
