Reactive oxygen species(ROS)and nitric oxide(NO)are two critical classes of signaling molecules that regulate plant development and stress responses.The intracellular level of S-nitrosoglutathione(GSNO),a major bioact...Reactive oxygen species(ROS)and nitric oxide(NO)are two critical classes of signaling molecules that regulate plant development and stress responses.The intracellular level of S-nitrosoglutathione(GSNO),a major bioactive NO species,is regulated by the highly conserved GSNO reductase(GSNOR).However,the molecular mechanisms underlying ROS-mediated regulation of GSNOR remain largely unclear.Here,we show that H_(2)O_(2)negatively regulates the activity of GSNOR1 during ovule development in Arabidopsis.S-sulfenylation of GSNOR1 at Cys-284 inhibits its enzymatic activity.A GSNOR1C284S mutation causes a reduction of the total SNO level in pistils,thereby disrupting NO homeostasis and eventually leading to defective ovule development.These findings illustrate a unique mechanism by which ROS regulates ovule development through S-sulfenylation-mediated inhibition of the GSNOR activity,thereby establishing a molecular link between ROS and NO signaling pathways in reproductive development.展开更多
Hyperactivation of the NLRP3 inflammasome has been implicated in the pathogenesis of numerous diseases.However,the precise molecular mechanisms that modulate the transcriptional regulation of NLRP3 remain largely unkn...Hyperactivation of the NLRP3 inflammasome has been implicated in the pathogenesis of numerous diseases.However,the precise molecular mechanisms that modulate the transcriptional regulation of NLRP3 remain largely unknown.In this study,we demonstrated that S-nitrosoglutathione reductase(GSNOR)deficiency in macrophages leads to significant increases in the Nlrp3 and Il-1βexpression levels and interleukin-1β(IL-1β)secretion in response to NLRP3 inflammasome stimulation.Furthermore,in vivo experiments utilizing Gsnor^(−/−)mice revealed increased disease severity in both lipopolysaccharide(LPS)-induced septic shock and dextran sodium sulfate(DSS)-induced colitis models.Additionally,we showed that both LPS-induced septic shock and DSS-induced colitis were ameliorated in Gsnor^(−/−)Nlrp3^(−/−)double-knockout(DKO)mice.Mechanistically,GSNOR deficiency increases the S-nitrosation of mitogen-activated protein kinase 14(MAPK14)at the Cys211 residue and augments MAPK14 kinase activity,thereby promoting Nlrp3 and Il-1βtranscription and stimulating NLRP3 inflammasome activity.Our findings suggested that GSNOR is a regulator of the NLRP3 inflammasome and that reducing the level of S-nitrosylated MAPK14 may constitute an effective strategy for alleviating diseases associated with NLRP3-mediated inflammation.展开更多
Ulva prolifera,the primary causative species of green tide,has garnered significant attention due to its robust growth and reproductive capacity under high salt stress.However,there has been relatively little research...Ulva prolifera,the primary causative species of green tide,has garnered significant attention due to its robust growth and reproductive capacity under high salt stress.However,there has been relatively little research on the regulation of high salt stress in this species.In this study,we observed that high salt stress suppressed the growth of U.prolifera and leading to the nitric oxide(NO)accumulation,along with increased gene expression levels and enzyme activity of S-nitrosoglutathione reductase(GSNOR).Treatment with GSNOR inhibitor resulted in elevated NO levels under high salt stress,accompanied by reduced activity of antioxidant enzymes and decreased glutathione(GSH)accumulation,making U.prolifera more sensitive to high salt stress.Conversely,NO scavenger treatment not only reduced NO levels,but also weakened the high salt stress tolerance of U.prolifera.Furthermore,using tandem mass tags(TMT)switch analysis and mass spectrometry,we observed a significant increase in S nitrosylated protein levels in U.prolifera under high salt stress,with further augmentation upon GSNOR inhibitor treatment.We also found high salt stress induced S-nitrosylation(SNO)of glutathione reductase(GR),which is negatively regulated by GSNOR,resulting in increased GR activity.Our results show that under short-term high salt stress,the elevated expression level of GSNOR avoided excessive accumulation of NO,and a certain amount of NO enhanced the activity of antioxidant enzymes through SNO modification,which improve the high salt stress tolerance of U.prolifera,whereas under long-term high salt stress,excessive NO was toxic to U.prolifera.展开更多
Cross talk between phytohormones, nitric oxide （NO）, and auxin has been implicated in the control of plant growth and development. Two recent reports indicate that NO promoted auxin signaling but inhibited auxin tra...Cross talk between phytohormones, nitric oxide （NO）, and auxin has been implicated in the control of plant growth and development. Two recent reports indicate that NO promoted auxin signaling but inhibited auxin transport probably through S-nitrosylation. However, genetic evidence for the effect of S-nitrosylation on auxin physiology has been lacking. In this study, we used a genetic approach to understand the broader role of S-nitrosylation in auxin physiology in Arabidopsis. We compared auxin signaling and transport in Col-0 and gsnorl-3, a loss-of-function GSNOR1 mutant defective in protein de-nitrosylation. Our results showed that auxin signaling was impaired in the gsnorl-3 mutant as revealed by significantly reduced DR5-GUS/ DR5-GFP accumulation and compromised degradation of AXR3NT-GUS, a useful reporter in interrogating auxin-mediated degradation of Aux/IAA by auxin receptors. In addition, polar auxin transport was compro- mised in gsnorl-3, which was correlated with universally reduced levels of PIN or GFP-PIN proteins in the roots of the mutant in a manner independent of transcription and 26S proteasome degradation. Our results suggest that S-nitrosylation and GSNORl-mediated de-nitrosylation contribute to auxin physiology, and impaired auxin signaling and compromised auxin transport are responsible for the auxin-related morpho- logical phenotypes displayed by the gsnorl-3 mutant.展开更多
Reactive oxygen signaling regulates numerous biological processes,including stress responses in plants.Redox sensors transduce reactive oxygen signals into cellular responses.Here,we present biochemical evidence that ...Reactive oxygen signaling regulates numerous biological processes,including stress responses in plants.Redox sensors transduce reactive oxygen signals into cellular responses.Here,we present biochemical evidence that a plant quiescin sulfhydryl oxidase homolog(QSOX1)is a redox sensor that negatively regulates plant immunity against a bacterial pathogen.The expression level of QSOX1 is inversely correlated with pathogen-induced reactive oxygen species(ROS)accumulation.Interestingly,QSOX1 both senses and regulates ROS levels by interactingn with and mediating redox regulation of S-nitrosoglutathione reductase,which,consistent with previous findings,influences reactive nitrogen-mediated regulation of ROS generation.Collectively,our data indicate that QSOX1 is a redox sensorthat negatively regulates plant immunity by linking reactive oxygen and reactive nitrogen signaling to limit ROS production.展开更多
Metabolism of S-nitrosoglutathione （GSNO）, a major biologically active nitric oxide （NO） species, is catalyzed by the evolutionally conserved GSNO reductase （GSNOR）. Previous studies showed that the Arabidopsis ...Metabolism of S-nitrosoglutathione （GSNO）, a major biologically active nitric oxide （NO） species, is catalyzed by the evolutionally conserved GSNO reductase （GSNOR）. Previous studies showed that the Arabidopsis GSNOR1/ HOT5 gene regulates salicylic acid signaling and thermotolerance by modulating the intracellular S-nitrosothiol level. Here, we report the characterization of the Arabidopsisparaquat resistant2-1 （par2-1） mutant that shows an anti-cell death phenotype. The production of superoxide in par2-1 is comparable to that of wild-type plants when treated by paraquat （1,1＇-dimethyl-4,4＇-bipyridinium dichloride）, suggesting that PAR2 acts downstream of superoxide to regulate cell death. PAR2, identified by positional cloning, is shown to be identical to GSNOR1/HOT5. The par2-1 mutant carries a missense mutation in a highly conserved glycine, which renders the mutant protein unstable. Compared to wild type, par2-1 mutant has a higher NO level, as revealed by staining with 4,5-diaminofluorescein diacetate. Consistent with this result, wild-type plants treated with an NO donor display resistance to paraquat. Interestingly, the GSNOR1/HOT5/PAR2 protein level, other than its steady-state mRNA level, is induced by paraquat, but is reduced by NO donors. Taken together, these results suggest that GSNOR1/HOT5/PAR2 plays an important role in regulating cell death in plant cells through modulating intracellular NO level.展开更多
Seed germination or dormancy status is strictly controlled by endogenous phytohormone and exogenous environment signals.Abscisic acid(ABA)is the important phytohormone to suppress seed germination.Ambient high tempera...Seed germination or dormancy status is strictly controlled by endogenous phytohormone and exogenous environment signals.Abscisic acid(ABA)is the important phytohormone to suppress seed germination.Ambient high temperature(HT)also suppressed seed germination,or called as secondary seed dormancy,through upregulating ABI5,the essential component of ABA signal pathway.Previous result shows that appropriate nitric oxide(NO)breaks seed dormancy through triggering S-nitrosoglutathion reductase(GSNOR1)-dependent S-nitrosylation modification of ABI5 protein,subsequently inducing the degradation of ABI5.Here we found that HT induced the degradation of GSNOR1 protein and reduced its activity,thus accumulated more reactive nitrogen species(RNS)to damage seeds viability.Furthermore,HT increased the S-nitrosylation modification of GSNOR1 protein,and triggered the degradation of GSNOR1,therefore stabilizing ABI5 to suppress seed germination.Consistently,the ABI5 protein abundance was lower in the transgenic line overexpressing GSNOR1,but higher in the gsnor mutant after HT stress.Genetic analysis showed that GSNOR1 affected seeds germination through ABI5 under HT.Taken together,our data reveals a new mechanism by which HT triggers the degradation of GSNOR1,and thus stabilizing ABI5 to suppress seed germination,such mechanism provides the possibility to enhance seed germination tolerance to HT through genetic modification of GNSOR1.展开更多
基金supported by grants from the National Natural Science Foundation of China(32170312,31830017,and 32200256)State Key Laboratory of Plant Genomics(SKLPG2023-22).
文摘Reactive oxygen species(ROS)and nitric oxide(NO)are two critical classes of signaling molecules that regulate plant development and stress responses.The intracellular level of S-nitrosoglutathione(GSNO),a major bioactive NO species,is regulated by the highly conserved GSNO reductase(GSNOR).However,the molecular mechanisms underlying ROS-mediated regulation of GSNOR remain largely unclear.Here,we show that H_(2)O_(2)negatively regulates the activity of GSNOR1 during ovule development in Arabidopsis.S-sulfenylation of GSNOR1 at Cys-284 inhibits its enzymatic activity.A GSNOR1C284S mutation causes a reduction of the total SNO level in pistils,thereby disrupting NO homeostasis and eventually leading to defective ovule development.These findings illustrate a unique mechanism by which ROS regulates ovule development through S-sulfenylation-mediated inhibition of the GSNOR activity,thereby establishing a molecular link between ROS and NO signaling pathways in reproductive development.
基金Yunnan Fundamental Research Project(202305AH340006)National Natural Science Foundation of China(32201018)+1 种基金Basic Research Program and Key Project of Yunnan Province(202301AW070013 and 202003AD150009)Youth Innovation Promotion Association(2023403).
文摘Hyperactivation of the NLRP3 inflammasome has been implicated in the pathogenesis of numerous diseases.However,the precise molecular mechanisms that modulate the transcriptional regulation of NLRP3 remain largely unknown.In this study,we demonstrated that S-nitrosoglutathione reductase(GSNOR)deficiency in macrophages leads to significant increases in the Nlrp3 and Il-1βexpression levels and interleukin-1β(IL-1β)secretion in response to NLRP3 inflammasome stimulation.Furthermore,in vivo experiments utilizing Gsnor^(−/−)mice revealed increased disease severity in both lipopolysaccharide(LPS)-induced septic shock and dextran sodium sulfate(DSS)-induced colitis models.Additionally,we showed that both LPS-induced septic shock and DSS-induced colitis were ameliorated in Gsnor^(−/−)Nlrp3^(−/−)double-knockout(DKO)mice.Mechanistically,GSNOR deficiency increases the S-nitrosation of mitogen-activated protein kinase 14(MAPK14)at the Cys211 residue and augments MAPK14 kinase activity,thereby promoting Nlrp3 and Il-1βtranscription and stimulating NLRP3 inflammasome activity.Our findings suggested that GSNOR is a regulator of the NLRP3 inflammasome and that reducing the level of S-nitrosylated MAPK14 may constitute an effective strategy for alleviating diseases associated with NLRP3-mediated inflammation.
基金Supported by the National Natural Science Foundation of China(No.42276100)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Ulva prolifera,the primary causative species of green tide,has garnered significant attention due to its robust growth and reproductive capacity under high salt stress.However,there has been relatively little research on the regulation of high salt stress in this species.In this study,we observed that high salt stress suppressed the growth of U.prolifera and leading to the nitric oxide(NO)accumulation,along with increased gene expression levels and enzyme activity of S-nitrosoglutathione reductase(GSNOR).Treatment with GSNOR inhibitor resulted in elevated NO levels under high salt stress,accompanied by reduced activity of antioxidant enzymes and decreased glutathione(GSH)accumulation,making U.prolifera more sensitive to high salt stress.Conversely,NO scavenger treatment not only reduced NO levels,but also weakened the high salt stress tolerance of U.prolifera.Furthermore,using tandem mass tags(TMT)switch analysis and mass spectrometry,we observed a significant increase in S nitrosylated protein levels in U.prolifera under high salt stress,with further augmentation upon GSNOR inhibitor treatment.We also found high salt stress induced S-nitrosylation(SNO)of glutathione reductase(GR),which is negatively regulated by GSNOR,resulting in increased GR activity.Our results show that under short-term high salt stress,the elevated expression level of GSNOR avoided excessive accumulation of NO,and a certain amount of NO enhanced the activity of antioxidant enzymes through SNO modification,which improve the high salt stress tolerance of U.prolifera,whereas under long-term high salt stress,excessive NO was toxic to U.prolifera.
文摘Cross talk between phytohormones, nitric oxide （NO）, and auxin has been implicated in the control of plant growth and development. Two recent reports indicate that NO promoted auxin signaling but inhibited auxin transport probably through S-nitrosylation. However, genetic evidence for the effect of S-nitrosylation on auxin physiology has been lacking. In this study, we used a genetic approach to understand the broader role of S-nitrosylation in auxin physiology in Arabidopsis. We compared auxin signaling and transport in Col-0 and gsnorl-3, a loss-of-function GSNOR1 mutant defective in protein de-nitrosylation. Our results showed that auxin signaling was impaired in the gsnorl-3 mutant as revealed by significantly reduced DR5-GUS/ DR5-GFP accumulation and compromised degradation of AXR3NT-GUS, a useful reporter in interrogating auxin-mediated degradation of Aux/IAA by auxin receptors. In addition, polar auxin transport was compro- mised in gsnorl-3, which was correlated with universally reduced levels of PIN or GFP-PIN proteins in the roots of the mutant in a manner independent of transcription and 26S proteasome degradation. Our results suggest that S-nitrosylation and GSNORl-mediated de-nitrosylation contribute to auxin physiology, and impaired auxin signaling and compromised auxin transport are responsible for the auxin-related morpho- logical phenotypes displayed by the gsnorl-3 mutant.
基金supported by grants from the"BioGreen21 Agri-Tech Inovation Program(project no.PJ015824 to S.Y.L.and PJ0159992021 to M.G.K.)",Rural Development Administration(RDA),South Koreaby the Basic Science Research Program through the National Research Foundation(NRF)of South Korea funded by the Ministry of Education(NRF-2018R1A6A3A11049525 to H.B.C.).
文摘Reactive oxygen signaling regulates numerous biological processes,including stress responses in plants.Redox sensors transduce reactive oxygen signals into cellular responses.Here,we present biochemical evidence that a plant quiescin sulfhydryl oxidase homolog(QSOX1)is a redox sensor that negatively regulates plant immunity against a bacterial pathogen.The expression level of QSOX1 is inversely correlated with pathogen-induced reactive oxygen species(ROS)accumulation.Interestingly,QSOX1 both senses and regulates ROS levels by interactingn with and mediating redox regulation of S-nitrosoglutathione reductase,which,consistent with previous findings,influences reactive nitrogen-mediated regulation of ROS generation.Collectively,our data indicate that QSOX1 is a redox sensorthat negatively regulates plant immunity by linking reactive oxygen and reactive nitrogen signaling to limit ROS production.
基金We thank Dr Gary Loake （University of Edinburgh, UK） for providing gsnor1-3 seeds. We are grateful to Drs Chuanyou Li, Shuhua Yang and Yiqin Wang for critically reading the manuscript. This study was supported by grants from the National Natural Science Foundation of China （30330360）, the Ministry of Science and Technology of China （2006AA 10A 112） and the Chinese Academy of Sciences （KSCX2-YW-N-015）.
文摘Metabolism of S-nitrosoglutathione （GSNO）, a major biologically active nitric oxide （NO） species, is catalyzed by the evolutionally conserved GSNO reductase （GSNOR）. Previous studies showed that the Arabidopsis GSNOR1/ HOT5 gene regulates salicylic acid signaling and thermotolerance by modulating the intracellular S-nitrosothiol level. Here, we report the characterization of the Arabidopsisparaquat resistant2-1 （par2-1） mutant that shows an anti-cell death phenotype. The production of superoxide in par2-1 is comparable to that of wild-type plants when treated by paraquat （1,1＇-dimethyl-4,4＇-bipyridinium dichloride）, suggesting that PAR2 acts downstream of superoxide to regulate cell death. PAR2, identified by positional cloning, is shown to be identical to GSNOR1/HOT5. The par2-1 mutant carries a missense mutation in a highly conserved glycine, which renders the mutant protein unstable. Compared to wild type, par2-1 mutant has a higher NO level, as revealed by staining with 4,5-diaminofluorescein diacetate. Consistent with this result, wild-type plants treated with an NO donor display resistance to paraquat. Interestingly, the GSNOR1/HOT5/PAR2 protein level, other than its steady-state mRNA level, is induced by paraquat, but is reduced by NO donors. Taken together, these results suggest that GSNOR1/HOT5/PAR2 plays an important role in regulating cell death in plant cells through modulating intracellular NO level.
基金funded by the National Natural Science Foundation of China(Grants No.31970289).
文摘Seed germination or dormancy status is strictly controlled by endogenous phytohormone and exogenous environment signals.Abscisic acid(ABA)is the important phytohormone to suppress seed germination.Ambient high temperature(HT)also suppressed seed germination,or called as secondary seed dormancy,through upregulating ABI5,the essential component of ABA signal pathway.Previous result shows that appropriate nitric oxide(NO)breaks seed dormancy through triggering S-nitrosoglutathion reductase(GSNOR1)-dependent S-nitrosylation modification of ABI5 protein,subsequently inducing the degradation of ABI5.Here we found that HT induced the degradation of GSNOR1 protein and reduced its activity,thus accumulated more reactive nitrogen species(RNS)to damage seeds viability.Furthermore,HT increased the S-nitrosylation modification of GSNOR1 protein,and triggered the degradation of GSNOR1,therefore stabilizing ABI5 to suppress seed germination.Consistently,the ABI5 protein abundance was lower in the transgenic line overexpressing GSNOR1,but higher in the gsnor mutant after HT stress.Genetic analysis showed that GSNOR1 affected seeds germination through ABI5 under HT.Taken together,our data reveals a new mechanism by which HT triggers the degradation of GSNOR1,and thus stabilizing ABI5 to suppress seed germination,such mechanism provides the possibility to enhance seed germination tolerance to HT through genetic modification of GNSOR1.
基金supported by grants from The National Key Research and Development Program of China(2017YFA0504000)The National Natural Science Foundation of China(31570857,91849203,31800969)~~
