Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifical...Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifically H_(2)O_(2)derived from roots and mediated by the respiratory burst oxidase homolog(NADPH),plays a significant role in regulating ion and plant hormone homeostasis in glycophytic plants,such as Arabidopsis.However,the extent to which root-derived H_(2)O_(2)fulfils similar functions in halophytic plants remains uncertain.Therefore,our study aimed to explore the potential contribution of root-sourced H_(2)O_(2)in delaying leaf senescence induced by high salinity,utilizing seashore paspalum as a model halophytic plant.The application of the NADPH-oxidase inhibitor DPI,coupled with a series of leaf senescence analyses,we revealed that root-derived H_(2)O_(2)significantly retards salt-induced leaf senescence.Furthermore,through the application of hormone analysis,lipidomics,ionomics,Non-invasive Micro-test Technology(NMT),and transcriptomics,we established that NADPH-dependent H_(2)O_(2)induced by salt stress in the roots was indispensable for maintaining the balance of the aging hormone,jasmonic acid(JA),and sodium ion homeostasis within this halophytic plant.Finally,by utilizing AtrbohD Arabidopsis mutants and virus-induced gene silencing(VIGs)in Paspalum vaginatum,we demonstrated the pivotal role played by root-sourced H_(2)O_(2)in upholding JA homeostasis and regulating JA-triggered leaf senescence in P.vaginatum.This study offers novel insights into the mechanisms that govern plant leaf senescence and its response to salinity-induced stress.展开更多
Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorl...Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.展开更多
The parasitic dodder(Cuscuta,Convolvulaceae)species have wide ranges of hosts.However,some plants,including the cultivated tomato(Solanum lycopersicum),have different degrees of resistance to Cuscuta.The cultivated to...The parasitic dodder(Cuscuta,Convolvulaceae)species have wide ranges of hosts.However,some plants,including the cultivated tomato(Solanum lycopersicum),have different degrees of resistance to Cuscuta.The cultivated tomato plants activate a strong hypersensitive response(HR)where Cuscuta haustoria penetrate stems of cultivated tomato,but the underlying mechanisms by which the cultivated tomato perceives Cuscuta and activates resistance remain unclear.In this study,we show that the phytohormones jasmonic acid(JA)and salicylic acid(SA)in cultivated tomato stems were highly induced by Cuscuta australis parasitization.Genetic analyses and experiments of supplementation of JA or SA indicated that the JA and SA pathway not only are both required for activation of HR against Cuscuta parasitization but also function in non-HR-based resistance.The Cuscuta Receptor 1(CuRe1),which is a leucine-rich repeat receptor-like protein,and suppressor of BAK1-interacting receptor kinase(SOBIR1)and SOBIR1-like,two adaptor kinases,are also important for HR-based and non-HR-based resistance.Importantly,we found that the JA and SA pathway both transcriptionally regulate CuRe1.However,in the cure1 mutants,JA and SA levels were still normally induced by C.australis parasitization.We propose a linear model that an unknown receptor perceives Cuscuta parasitization and thus triggers accumulation of JA and SA,which in turn induce the transcription of CuRe1,and CuRe1 and SOBIR1/SOBIR1-like thereby activate HR-based and non-HR-based resistance to Cuscuta.This study underscores the important roles of hormone signaling and resistance(R)genes in host plant-parasitic plant interactions.展开更多
Ca^(2+)signaling plays crucial roles in plant stress responses,including defense against insects.To counteract insect feeding,different parts of a plant deploy systemic signaling to communicate and coordinate defense ...Ca^(2+)signaling plays crucial roles in plant stress responses,including defense against insects.To counteract insect feeding,different parts of a plant deploy systemic signaling to communicate and coordinate defense responses,but little is known about the underlying mechanisms.In this study,micrografting,in vivo imaging of Ca^(2+)and reactive oxygen species(ROS),quantification of jasmonic acid(JA)and defensive metabolites,and bioassay were used to study how Arabidopsis seedlings regulate systemic responses in leaves after hypocotyls are wounded.We show that wounding hypocotyls rapidly activated both Ca^(2+)and ROS signals in leaves.RBOHD,which functions to produce ROS,along with two glutamate receptors GLR3.3 and GLR3.6,but not individually RBOHD or GLR3.3 and GLR3.6,in hypocotyls regulate the dynamics of systemic Ca^(2+)signals in leaves.In line with the systemic Ca^(2+)signals,after wounding hypocotyl,RBOHD,GLR3.3,and GLR3.6 in hypocotyl also cooperatively regulate the transcriptome,hormone jasmonic acid,and defensive secondary metabolites in leaves of Arabidopsis seedlings,thus controlling the systemic resistance to insects.Unlike leaf-to-leaf systemic signaling,this study reveals the unique regulation of wounding-induced hypocotyl-to-leaf systemic signaling and sheds new light on how different plant organs use complex signaling pathways to modulate defense responses.展开更多
Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohorm...Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohormone jasmonic acid(JA)plays crucial roles in the response to rice blast fungus.However,how M.oryzae disrupts JA-mediated resistance in rice is not well understood.In this study,we identify a new effector,a chloroplast-targeting protein(MoCHT1),from M.oryzae.Knocking out MoCHT1 decreases virulence,whereas heterologous expression of MoCHT1 in rice compromises disease resistance.MoCHT1 interacts with a rice LESION AND LAMINA BENDING(OsLLB)protein,a negative regulator of JA biosynthesis in the chloroplast.Loss-of-function of Os LLB leads to increased JA accumulation,thereby improving resistance to rice blast.The interaction between MoCHT1 and OsLLB results in the inhibition of OsLLB degradation,consequently reducing JA accumulation,thereby impairing JA content and decreasing plant disease resistance.Overall,this study reveals the molecular mechanism by which M.oryzae utilizes MoCHT1 to subvert rice JA signaling,broadening our understanding of how pathogens circumvent host immune responses by manipulating plant defense hormone biosynthesis.展开更多
The relationship between the effect of exogenous jasmonic acid (JA) on the induction of secondary laticifer differentiation and the distribution of JA in the seedling of Hevea brasiliensis Mull. Arg. was investigated ...The relationship between the effect of exogenous jasmonic acid (JA) on the induction of secondary laticifer differentiation and the distribution of JA in the seedling of Hevea brasiliensis Mull. Arg. was investigated with the aid of experimental morphological and radioisotope technique. Most radioactivity of H-3-JA sustained in treated site within one hour while no radioactivity was detected in new shoot and the radioactivity in upper leaf was much less than that in the parts below the treated site, suggesting that JA was mainly transported downwards in the shoot of H brasiliensis. Mechanical wounding hindered the entrance of exogenous JA remarkably while held back the entered JA to the regions around wounded site. The effect of exogenous JA and mechanical wounding on the induction of the secondary laticifer differentiation was limited to treated site where high level of JA was expected. Mechanical wounding reduced the effect of exogenous JA on the differentiation of secondary laticifer, which could be ascribed to the hindrance of mechanical wounding to the entrance of exogenous JA. It was concluded from the combined data that a high accumulation of JA was required for inducing the secondary laticifer differentiation in H. brasiliensis.展开更多
Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedl...Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedling were studied with radioisotope technique. The results showed that 3H-JA could be transported up or down at the rate of 4-5 cm·min -1 following feeding into root or shoot tip. The transport of 3H-JA in shoot reached a relative stable rate at 30 min after being fed through root. Wounding by scorch in the youngest leaf caused an increase in the transport of 3H-JA from root to shoot and enhanced the distribution of 3H-JA in the wounded leaf. However, distribution of 3H-JA in unwounded leaves increased after 5 h being fed through the youngest leaf. It was noticed that wounding improved accumulation of 3H-JA in abaxial epidermis. Consistent results were obtained: wounding prevented transport of 3H-JA out from the youngest leaf to root; These observations suggest that JA plays an important role as a defense signal and might be involved in the regulation of the stomatal movement in response to wounding stress.展开更多
[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were ex...[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were explored by real time quantitative RT-PCR technology.[Result]JA induced the expression of LeWRKY1,but SA did not.LeWRKY1 expression was up-regulated under B.cinerea infection.[Conclusion]LeWRKY1 might be involved in the tomato defense response to B.cinerea through JA dependent but SA independent signal pathway.展开更多
[Objective] This experiment aimed to evaluate the effects of calcium and Jasmonic acid（JA） on the expression of CBF in spinach. [Methods] The seedlings of spinach were treated with low temperature （4 ℃）, JA or A2...[Objective] This experiment aimed to evaluate the effects of calcium and Jasmonic acid（JA） on the expression of CBF in spinach. [Methods] The seedlings of spinach were treated with low temperature （4 ℃）, JA or A23187, then used for detecting the expression of CBF by northern blotting. [Results] The results showed that the CBF expression was regulated by low temperature and JA positively. [Conclusions] Low temperature may increase the JA content of the cell firstly, then JA induced the increase of cytosolic calcium concentration （[Ca2＋]cyt）, and the JA induced Ca2＋ transmitted the low temperature signal through CaM or CaM related proteins, regulating the CBF expression.展开更多
[Objective] This study was to investigate the role of IP3 sensitive calcium channel in the JA-induced calcium mobilization pathway.[Method] Arabidopsis thaliana leaves were labeled by Fluorescent probe Fluo-3/AM under...[Objective] This study was to investigate the role of IP3 sensitive calcium channel in the JA-induced calcium mobilization pathway.[Method] Arabidopsis thaliana leaves were labeled by Fluorescent probe Fluo-3/AM under low temperature at 4 ℃ to measure the fluorescent intensity of intracellular Ca2＋ which was pretreated with heparin on jasmonic acid（JA）-induced.[Results] When A.thaliana leaf cells were pretreated with 10,50 or 100 ng/ml heparin,intercellular free Ca2＋ fluorescence intensity was reduced in comparison with negative control.Once the heparin-pretreated A.thaliana leaf cells were stimulated with 100 μmol/L JA,intercellular Ca2＋ fluorescence intensity increased gradually and tended to be stable at a degree equivalent with that in negative control.[Conclusion] The experiment showed that the pretreatment with heparin could inhibit the increase of the intracellular Ca2＋ concentration significantly which JA-induced in leaves of Arabidopsis thaliana.展开更多
Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic eviden...Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic evidence to show that the Arabidopsis thaliana NAC family proteins ANAC019 and ANAC055 might function as transcription activators to regulate JA-induced expression of defense genes. The role of the two NAC genes in JA signaling was examined with the anacO19 anac055 double mutant and with transgenic plants overexpressing ANACO19 or ANAC055. The anacO19 anac055 double mutant plants showed attenuated JA-induced VEGETATIVE STORAGE PROTEIN1 （VSP1） and LIPOXYGENASE2 （LOX2） expression, whereas transgenic plants overexpressing the two NAC genes showed enhanced JA-induced VSP1 and LOX2 expression. That the JA-induced expression of the two NAC genes depends on the function of COIl and AtMYC2, together with the finding that overexpression of ANACO19 partially rescued the JA-related phenotype of the atmyc2-2 mutant, has led us to a hypothesis that the two NAC proteins act downstream of AtMYC2 to regulate JA-signaled defense responses. Further evidence to substantiate this idea comes from the observation that the response of the anacO19 anac055 double mutant to a necrotrophic fungus showed high similarity to that of the atmyc2-2 mutant.展开更多
The plant hormone jasmonic acid （JA） plays a central role in plant defense against herbivores. Herbivore damage elicits a rapid and transient JA burst in the wounded leaves and JA functions as a signal to mediate th...The plant hormone jasmonic acid （JA） plays a central role in plant defense against herbivores. Herbivore damage elicits a rapid and transient JA burst in the wounded leaves and JA functions as a signal to mediate the accumulation of various secondary metabolites that confer resistance to herbivores. Nicotiana attenuata is a wild tobacco species that inhabits western North America. More than fifteen years of study and its unique interaction with the specialist herbivore insect Manduca sexta have made this plant one of the best models for studying plant-herbivore interactions. Here we review the recent progress in understanding the elicitation of JA accumulation by herbivore-specific elicitors, the regulation of JA biosynthesis, JA signaling, and the herbivore-defense traits in N. attenuata.展开更多
Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the g...Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the genes encoding the biosynthesis and metabolism of abscisic acid(ABA)and jasmonic acid(JA),as well as genes involved in the ABA and JA signaling pathways were up-regulated by drought priming.Endogenous concentrations of JA and ABA increased following drought priming.The interplay between JA and ABA in plant responses to drought priming was further investigated using inhibitors of ABA and JA biosynthesis.Application of fluridone(FLU)or nordihydroguaiaretic acid(NDGA)to primed plants resulted in lower chlorophyll-fluorescence parameters and activities of superoxide dismutase and glutathione reductase,and higher cell membrane damage,compared to primed plants(PD)under drought stress.NDGA+ABA,but not FLU+JA,restored priming-induced tolerance,as indicated by a finding of no significant difference from PD under drought stress.Under drought priming,NDGA induced the suppression of ABA accumulation,while FLU did not affect JA accumulation.These results were consistent with the expression of genes involved in the biosynthesis of ABA and JA.They suggest that ABA and JA are required for priming-induced drought tolerance in wheat,with JA acting upstream of ABA.展开更多
The well-known detrimental effects of cadmium （Cd） on plants are chloroplast destruction, photosynthetic pigment inhibition, imbalance of essential plant nutrients, and membrane damage. Jasmonic acid （JA） is an al...The well-known detrimental effects of cadmium （Cd） on plants are chloroplast destruction, photosynthetic pigment inhibition, imbalance of essential plant nutrients, and membrane damage. Jasmonic acid （JA） is an alleviator against different stresses such as salinity and drought. However, the functional attributes of JA in plants such as the interactive effects of JA application and Cd on rapeseed in response to heavy metal stress remain unclear. JA at 50 pmol/L was observed in literature to have senescence effects in plants. In the present study, 25 pmol/L JA is ob- served to be a ＂stress ameliorating molecule＂ by improving the tolerance of rapeseed plants to Cd toxicity. JA reduces the Cd uptake in the leaves, thereby reducing membrane damage and malondialdehyde content and increasing the essential nutrient uptake. Furthermore, JA shields the chloroplast against the damaging effects of Cd, thereby in- creasing gas exchange and photosynthetic pigments. Moreover, JA modulates the antioxidant enzyme activity to strengthen the internal defense system. Our results demonstrate the function of JA in alleviating Cd toxicity and its underlying mechanism. Moreover, JA attenuates the damage of Cd to plants. This study enriches our knowledge regarding the use of and protection provided by JA in Cd stress.展开更多
Cotton fibers are single cells originating in the epidermis of cotton ovules,and serve as the largest natural fiber source for the textile industry.In theory,all epidermal cells have the potential to develop into fibe...Cotton fibers are single cells originating in the epidermis of cotton ovules,and serve as the largest natural fiber source for the textile industry.In theory,all epidermal cells have the potential to develop into fibers,but only 15%–25%of epidermis cells develop into commercially viable lint fibers.We previously showed that Gh Lac1 participates in cotton defense against biotic stress.Here we report that Gh Lac1 also has a role in cotton fiber development.Gh Lac1 RNAi lines in cotton showed increased differentiation of fiber initials from epidermis and shortened fiber length,resulting in unchanged lint percentage.Suppression of Gh Lac1 expression led to constitutively hyperaccumulated jasmonic acid(JA)and flavonoids in ovules and fiber cells.In vitro ovule culture experiments confirmed the distinct roles of JA and flavonoids in fiber initiation and elongation,and showed that fiber development is spatially regulated by these chemicals:the increased fiber initiation in Gh Lac1 RNAi lines is caused by hyperaccumulated JA and rutin content during the fiber initiation stage and shortened fiber length is caused by constitutively increased JA and naringenin content during the fiber elongation stage.展开更多
Jasmonates are class of plant growth regulators act as signal molecule that intercede various components in physiological and metabolic regulation, stress responses and possibly communication through signal transducti...Jasmonates are class of plant growth regulators act as signal molecule that intercede various components in physiological and metabolic regulation, stress responses and possibly communication through signal transduction. Oxidative stress due to heavy metal exposure stimulates synthesis and activity of antioxidant metabolites and enhances antioxidant enzyme activities that could protect plant tissues. The aim of this study was to investigate the exogenous effect of JA at seed level which can transduce throughout seedling growth and regulate antioxidant activities such as superoxide dismutase (SOD;EC 1.15.1.1) and guaiacol peroxidase (POD;EC 1.11.1.7) in 12 days old seedlings of pigeon pea (Cajanus cajan (L.) Millsp.) in presence and/or absence of copper. The activity of SOD and POD increased significantly in presence of Cu2+ after seed priming with JA. JA also helps in chlorophyll and carotenoid accumulation and neutralizes the toxic effect of Cu2+ on seedlings. This is the first report of JA effect on photosynthetic pigment accumulation and H2O2 mitigating enzymes i.e. SOD and POD and it could be recommended that seed priming with JA help in ameliorating toxic effect of Cu2+.展开更多
Cotton(Gossypium spp.) yield is reduced by stress. In this study, high temperature(HT) suppressed the expression of the jasmonic acid(JA) biosynthesis gene allene oxide cyclase 2(GhAOC2), reducing JA content and causi...Cotton(Gossypium spp.) yield is reduced by stress. In this study, high temperature(HT) suppressed the expression of the jasmonic acid(JA) biosynthesis gene allene oxide cyclase 2(GhAOC2), reducing JA content and causing male sterility in the cotton HT-sensitive line H05. Anther sterility was reversed by exogenous application of methyl jasmonate(MeJA) to early buds. To elucidate the role of GhAOC2 in JA biosynthesis and identify its putative contribution to the anther response to HT, we created gene knockout cotton plants using the CRISPR/Cas9 system. Ghaoc2 mutant lines showed male-sterile flowers with reduced JA content in the anthers at the tetrad stage(TS), tapetum degradation stage(TDS), and anther dehiscence stage(ADS). Exogenous application of MeJA to early mutant buds(containing TS or TDS anthers) rescued the sterile pollen and indehiscent anther phenotypes, while ROS signals were reduced in ADS anthers. We propose that HT downregulates the expression of GhAOC2 in anthers, reducing JA biosynthesis and causing excessive ROS accumulation in anthers, leading to male sterility. These findings suggest exogenous JA application as a strategy for increasing male fertility in cotton under HT.展开更多
To explore the regulatory effects of jasmonic acid （JA） on the expression of the genes involved in capsaicin biosynthesis pathway, the mRNA expression of the genes was determined by fluorescence-based quantitative P...To explore the regulatory effects of jasmonic acid （JA） on the expression of the genes involved in capsaicin biosynthesis pathway, the mRNA expression of the genes was determined by fluorescence-based quantitative PCR 0, 4, 12, 24 and 48 h after chili peppers （Capsicum annuum var. conoides） were treated with 100 μmol/L JA, and the content of capsaicin was measured by high performance liquid chromatography （HPLC） 0, 1, 3, 6, 10 and 15 d after JA treatment. The results showed that JA upregulated the mRNA levels of pal, C4h, Comt, 4Cl, Hct, Paint, Bcat, FatA and pun1 in chili pepper, thus promoting the synthesis of capsaicin to different extents.展开更多
Plant male reproduction is a fine-tuned developmental process that is susceptible to stressful environments and influences crop grain yields.Phytohormone signaling functions in control of plant normal growth and devel...Plant male reproduction is a fine-tuned developmental process that is susceptible to stressful environments and influences crop grain yields.Phytohormone signaling functions in control of plant normal growth and development as well as in response to external stresses,but the interaction or crosstalk among phytohormone signaling,stress response,and male reproduction in plants remains poorly understood.Cross-species comparison among 514 stress-response transcriptomic libraries revealed that ms33-6038,a genic male sterile mutant deficient in the Zm Ms33/Zm GPAT6 gene,displayed an excessive drought stress-like transcriptional reprogramming in anthers triggered mainly by disturbed jasmonic acid(JA)homeostasis.An increased level of JA appeared in Zm Ms33-deficient anthers at both meiotic and postmeiotic stages and activated genes involved in JA biosynthesis and signaling as well as genes functioning in JA-mediated drought response.Excessive accumulation of JA elevated expression level of a gene encoding a WRKY transcription factor that activated the Zm Ms33 promoter.These findings reveal a feedback loop of Zm Ms33-JA-WRKY-Zm Ms33 in controlling male sterility and JA-mediated stress response in maize,shedding light on the crosstalk of stress response and male sterility mediated by phytohormone homeostasis and signaling.展开更多
基金supported by the Project funded by the Natural Science Foundation of Hainan Province(Grant No.322QN248)the National Natural Science Foundation of China(Grant Nos.32401488,32060409,32371782 and 32460358)+3 种基金the Innovational Fund for Scientific and Technological Personnel of Hainan Province(Grant No.KJRC 2023C21)the Hainan High-level Talents Project(Grant No.321RC475)Collaborative Innovation Center Project of Nanfan and High-Efficiency Tropical Agriculture in Hainan University(XTCX2022NYB08)Collaborative Innovation Center Project of Ecological Civilization in Hainan University(XTCX2022STC10).
文摘Improving salt tolerance and mitigating senescence in the presence of high salinity are crucial for sustaining agricultural productivity.Previous research has demonstrated that hydrogen peroxide(H_(2)O_(2)),specifically H_(2)O_(2)derived from roots and mediated by the respiratory burst oxidase homolog(NADPH),plays a significant role in regulating ion and plant hormone homeostasis in glycophytic plants,such as Arabidopsis.However,the extent to which root-derived H_(2)O_(2)fulfils similar functions in halophytic plants remains uncertain.Therefore,our study aimed to explore the potential contribution of root-sourced H_(2)O_(2)in delaying leaf senescence induced by high salinity,utilizing seashore paspalum as a model halophytic plant.The application of the NADPH-oxidase inhibitor DPI,coupled with a series of leaf senescence analyses,we revealed that root-derived H_(2)O_(2)significantly retards salt-induced leaf senescence.Furthermore,through the application of hormone analysis,lipidomics,ionomics,Non-invasive Micro-test Technology(NMT),and transcriptomics,we established that NADPH-dependent H_(2)O_(2)induced by salt stress in the roots was indispensable for maintaining the balance of the aging hormone,jasmonic acid(JA),and sodium ion homeostasis within this halophytic plant.Finally,by utilizing AtrbohD Arabidopsis mutants and virus-induced gene silencing(VIGs)in Paspalum vaginatum,we demonstrated the pivotal role played by root-sourced H_(2)O_(2)in upholding JA homeostasis and regulating JA-triggered leaf senescence in P.vaginatum.This study offers novel insights into the mechanisms that govern plant leaf senescence and its response to salinity-induced stress.
基金funded by the National Key Research and Development Plan of China(2023YFD1400300)National Natural Science Foundation of China(U23A6006,32270149,32272555)+1 种基金Zhejiang Provincial Natural Science Foundation(LZ22C140001)the Ningbo Major Research and Development Plan Project(2023Z124).
文摘Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.
基金supported by National Natural Science Foundation of China(32270314(GS))the Key Project of Applied Basic Research Program of Yunnan(202201AS070056(JW),202301AS070064(GS))Yunnan Revitalization Talent Support Program“Yunling Scholar”Project(JW),Chinese Academy of Sciences(CAS)Light of West China Program(GS),Yunnan Revitalization Talent Support Program“Young Talents”Project(XDYC-QNRC-2022-0001(GS)).
文摘The parasitic dodder(Cuscuta,Convolvulaceae)species have wide ranges of hosts.However,some plants,including the cultivated tomato(Solanum lycopersicum),have different degrees of resistance to Cuscuta.The cultivated tomato plants activate a strong hypersensitive response(HR)where Cuscuta haustoria penetrate stems of cultivated tomato,but the underlying mechanisms by which the cultivated tomato perceives Cuscuta and activates resistance remain unclear.In this study,we show that the phytohormones jasmonic acid(JA)and salicylic acid(SA)in cultivated tomato stems were highly induced by Cuscuta australis parasitization.Genetic analyses and experiments of supplementation of JA or SA indicated that the JA and SA pathway not only are both required for activation of HR against Cuscuta parasitization but also function in non-HR-based resistance.The Cuscuta Receptor 1(CuRe1),which is a leucine-rich repeat receptor-like protein,and suppressor of BAK1-interacting receptor kinase(SOBIR1)and SOBIR1-like,two adaptor kinases,are also important for HR-based and non-HR-based resistance.Importantly,we found that the JA and SA pathway both transcriptionally regulate CuRe1.However,in the cure1 mutants,JA and SA levels were still normally induced by C.australis parasitization.We propose a linear model that an unknown receptor perceives Cuscuta parasitization and thus triggers accumulation of JA and SA,which in turn induce the transcription of CuRe1,and CuRe1 and SOBIR1/SOBIR1-like thereby activate HR-based and non-HR-based resistance to Cuscuta.This study underscores the important roles of hormone signaling and resistance(R)genes in host plant-parasitic plant interactions.
基金National Natural Science Foundation of China(U23A20199)Yunnan Revitalization Talent Support Program“Yunling Scholar”and Yunnan Fundamental Research Projects(202201AS070056)。
文摘Ca^(2+)signaling plays crucial roles in plant stress responses,including defense against insects.To counteract insect feeding,different parts of a plant deploy systemic signaling to communicate and coordinate defense responses,but little is known about the underlying mechanisms.In this study,micrografting,in vivo imaging of Ca^(2+)and reactive oxygen species(ROS),quantification of jasmonic acid(JA)and defensive metabolites,and bioassay were used to study how Arabidopsis seedlings regulate systemic responses in leaves after hypocotyls are wounded.We show that wounding hypocotyls rapidly activated both Ca^(2+)and ROS signals in leaves.RBOHD,which functions to produce ROS,along with two glutamate receptors GLR3.3 and GLR3.6,but not individually RBOHD or GLR3.3 and GLR3.6,in hypocotyls regulate the dynamics of systemic Ca^(2+)signals in leaves.In line with the systemic Ca^(2+)signals,after wounding hypocotyl,RBOHD,GLR3.3,and GLR3.6 in hypocotyl also cooperatively regulate the transcriptome,hormone jasmonic acid,and defensive secondary metabolites in leaves of Arabidopsis seedlings,thus controlling the systemic resistance to insects.Unlike leaf-to-leaf systemic signaling,this study reveals the unique regulation of wounding-induced hypocotyl-to-leaf systemic signaling and sheds new light on how different plant organs use complex signaling pathways to modulate defense responses.
基金funded by the Biological Breeding-National Science and Technology Major Projects(2023ZD04070)the National Natural Science Foundation of China(31970284,31900385)+1 种基金the Fujian Provincial Science and Technology Key Project(2022NZ030014)the Natural Science Foundation of Fujian Province,China(2023J01483,2022J01616)。
文摘Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohormone jasmonic acid(JA)plays crucial roles in the response to rice blast fungus.However,how M.oryzae disrupts JA-mediated resistance in rice is not well understood.In this study,we identify a new effector,a chloroplast-targeting protein(MoCHT1),from M.oryzae.Knocking out MoCHT1 decreases virulence,whereas heterologous expression of MoCHT1 in rice compromises disease resistance.MoCHT1 interacts with a rice LESION AND LAMINA BENDING(OsLLB)protein,a negative regulator of JA biosynthesis in the chloroplast.Loss-of-function of Os LLB leads to increased JA accumulation,thereby improving resistance to rice blast.The interaction between MoCHT1 and OsLLB results in the inhibition of OsLLB degradation,consequently reducing JA accumulation,thereby impairing JA content and decreasing plant disease resistance.Overall,this study reveals the molecular mechanism by which M.oryzae utilizes MoCHT1 to subvert rice JA signaling,broadening our understanding of how pathogens circumvent host immune responses by manipulating plant defense hormone biosynthesis.
文摘The relationship between the effect of exogenous jasmonic acid (JA) on the induction of secondary laticifer differentiation and the distribution of JA in the seedling of Hevea brasiliensis Mull. Arg. was investigated with the aid of experimental morphological and radioisotope technique. Most radioactivity of H-3-JA sustained in treated site within one hour while no radioactivity was detected in new shoot and the radioactivity in upper leaf was much less than that in the parts below the treated site, suggesting that JA was mainly transported downwards in the shoot of H brasiliensis. Mechanical wounding hindered the entrance of exogenous JA remarkably while held back the entered JA to the regions around wounded site. The effect of exogenous JA and mechanical wounding on the induction of the secondary laticifer differentiation was limited to treated site where high level of JA was expected. Mechanical wounding reduced the effect of exogenous JA on the differentiation of secondary laticifer, which could be ascribed to the hindrance of mechanical wounding to the entrance of exogenous JA. It was concluded from the combined data that a high accumulation of JA was required for inducing the secondary laticifer differentiation in H. brasiliensis.
文摘Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedling were studied with radioisotope technique. The results showed that 3H-JA could be transported up or down at the rate of 4-5 cm·min -1 following feeding into root or shoot tip. The transport of 3H-JA in shoot reached a relative stable rate at 30 min after being fed through root. Wounding by scorch in the youngest leaf caused an increase in the transport of 3H-JA from root to shoot and enhanced the distribution of 3H-JA in the wounded leaf. However, distribution of 3H-JA in unwounded leaves increased after 5 h being fed through the youngest leaf. It was noticed that wounding improved accumulation of 3H-JA in abaxial epidermis. Consistent results were obtained: wounding prevented transport of 3H-JA out from the youngest leaf to root; These observations suggest that JA plays an important role as a defense signal and might be involved in the regulation of the stomatal movement in response to wounding stress.
基金Supported by Beijing Nature Science Foundation(5102015)~~
文摘[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were explored by real time quantitative RT-PCR technology.[Result]JA induced the expression of LeWRKY1,but SA did not.LeWRKY1 expression was up-regulated under B.cinerea infection.[Conclusion]LeWRKY1 might be involved in the tomato defense response to B.cinerea through JA dependent but SA independent signal pathway.
基金Supported by Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality(PXM2006-014207-021798)Project of Organization Department of Beijing Municipal Party(20042D0502108)~~
文摘[Objective] This experiment aimed to evaluate the effects of calcium and Jasmonic acid（JA） on the expression of CBF in spinach. [Methods] The seedlings of spinach were treated with low temperature （4 ℃）, JA or A23187, then used for detecting the expression of CBF by northern blotting. [Results] The results showed that the CBF expression was regulated by low temperature and JA positively. [Conclusions] Low temperature may increase the JA content of the cell firstly, then JA induced the increase of cytosolic calcium concentration （[Ca2＋]cyt）, and the JA induced Ca2＋ transmitted the low temperature signal through CaM or CaM related proteins, regulating the CBF expression.
基金Supported by National Natural Science Foundation of China(30700428,30911130166)Natural Science Foundation of Beijing Municipality(5072009)The New Star Plan of Science and Technology in Beijing Municipality(2006B26)~~
文摘[Objective] This study was to investigate the role of IP3 sensitive calcium channel in the JA-induced calcium mobilization pathway.[Method] Arabidopsis thaliana leaves were labeled by Fluorescent probe Fluo-3/AM under low temperature at 4 ℃ to measure the fluorescent intensity of intracellular Ca2＋ which was pretreated with heparin on jasmonic acid（JA）-induced.[Results] When A.thaliana leaf cells were pretreated with 10,50 or 100 ng/ml heparin,intercellular free Ca2＋ fluorescence intensity was reduced in comparison with negative control.Once the heparin-pretreated A.thaliana leaf cells were stimulated with 100 μmol/L JA,intercellular Ca2＋ fluorescence intensity increased gradually and tended to be stable at a degree equivalent with that in negative control.[Conclusion] The experiment showed that the pretreatment with heparin could inhibit the increase of the intracellular Ca2＋ concentration significantly which JA-induced in leaves of Arabidopsis thaliana.
基金Acknowledgments We are grateful to Dr Xinnian Dong （Duke University, Durham, NC, USA） for critical reading of the manuscript and valuable suggestions. We thank Dr Jianmin Zhou （National Institute of Biological Sciences, Beijing, China） for providing the fungus strain Botrytis cinerea, Dr Salome Prat （Institut de Biologia Molecular de Barcelona, Barcelona, Spain） for providing homozygous atmyc2-2 （T-DNA insertion line SALK_083483） seeds and Dr Daoxin Xie （Tsinghua University, Beijing, China） for providing the coil-I seeds. This work was supported by grants from The National Natural Science Foundation of China （30530440）, The Ministry of Science and Technology of China （2006CB 102004, 2006AA10A 116）, and The Chinese Academy of Sciences （KSCX2-YW-N-045）.
文摘Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic evidence to show that the Arabidopsis thaliana NAC family proteins ANAC019 and ANAC055 might function as transcription activators to regulate JA-induced expression of defense genes. The role of the two NAC genes in JA signaling was examined with the anacO19 anac055 double mutant and with transgenic plants overexpressing ANACO19 or ANAC055. The anacO19 anac055 double mutant plants showed attenuated JA-induced VEGETATIVE STORAGE PROTEIN1 （VSP1） and LIPOXYGENASE2 （LOX2） expression, whereas transgenic plants overexpressing the two NAC genes showed enhanced JA-induced VSP1 and LOX2 expression. That the JA-induced expression of the two NAC genes depends on the function of COIl and AtMYC2, together with the finding that overexpression of ANACO19 partially rescued the JA-related phenotype of the atmyc2-2 mutant, has led us to a hypothesis that the two NAC proteins act downstream of AtMYC2 to regulate JA-signaled defense responses. Further evidence to substantiate this idea comes from the observation that the response of the anacO19 anac055 double mutant to a necrotrophic fungus showed high similarity to that of the atmyc2-2 mutant.
基金the Max Planck Society for financing the projects during our work at the Max Planck Institute for Chemical Ecologypart supported by the National Natural Science Foundation of China(Grant No.31201527) to L.Wang
文摘The plant hormone jasmonic acid （JA） plays a central role in plant defense against herbivores. Herbivore damage elicits a rapid and transient JA burst in the wounded leaves and JA functions as a signal to mediate the accumulation of various secondary metabolites that confer resistance to herbivores. Nicotiana attenuata is a wild tobacco species that inhabits western North America. More than fifteen years of study and its unique interaction with the specialist herbivore insect Manduca sexta have made this plant one of the best models for studying plant-herbivore interactions. Here we review the recent progress in understanding the elicitation of JA accumulation by herbivore-specific elicitors, the regulation of JA biosynthesis, JA signaling, and the herbivore-defense traits in N. attenuata.
基金supported by the National Key Research and Development Program of China(2016YFD0300107)the National Natural Science Foundation of China(31771693,U1803235)+3 种基金the Fundamental Research Funds for the Central Universities(KYZ201807)the China Agricultural Research System(CARS-03)the Jiangsu Collaborative Innovation Center for Modern Crop Production(JCIC-MCP)the 111 Project(B16026)。
文摘Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the genes encoding the biosynthesis and metabolism of abscisic acid(ABA)and jasmonic acid(JA),as well as genes involved in the ABA and JA signaling pathways were up-regulated by drought priming.Endogenous concentrations of JA and ABA increased following drought priming.The interplay between JA and ABA in plant responses to drought priming was further investigated using inhibitors of ABA and JA biosynthesis.Application of fluridone(FLU)or nordihydroguaiaretic acid(NDGA)to primed plants resulted in lower chlorophyll-fluorescence parameters and activities of superoxide dismutase and glutathione reductase,and higher cell membrane damage,compared to primed plants(PD)under drought stress.NDGA+ABA,but not FLU+JA,restored priming-induced tolerance,as indicated by a finding of no significant difference from PD under drought stress.Under drought priming,NDGA induced the suppression of ABA accumulation,while FLU did not affect JA accumulation.These results were consistent with the expression of genes involved in the biosynthesis of ABA and JA.They suggest that ABA and JA are required for priming-induced drought tolerance in wheat,with JA acting upstream of ABA.
基金Project supported by the National Basic Research Program(973)of China(No.2015CB150205)the National Natural Science Foundation of China(No.31671597)
文摘The well-known detrimental effects of cadmium （Cd） on plants are chloroplast destruction, photosynthetic pigment inhibition, imbalance of essential plant nutrients, and membrane damage. Jasmonic acid （JA） is an alleviator against different stresses such as salinity and drought. However, the functional attributes of JA in plants such as the interactive effects of JA application and Cd on rapeseed in response to heavy metal stress remain unclear. JA at 50 pmol/L was observed in literature to have senescence effects in plants. In the present study, 25 pmol/L JA is ob- served to be a ＂stress ameliorating molecule＂ by improving the tolerance of rapeseed plants to Cd toxicity. JA reduces the Cd uptake in the leaves, thereby reducing membrane damage and malondialdehyde content and increasing the essential nutrient uptake. Furthermore, JA shields the chloroplast against the damaging effects of Cd, thereby in- creasing gas exchange and photosynthetic pigments. Moreover, JA modulates the antioxidant enzyme activity to strengthen the internal defense system. Our results demonstrate the function of JA in alleviating Cd toxicity and its underlying mechanism. Moreover, JA attenuates the damage of Cd to plants. This study enriches our knowledge regarding the use of and protection provided by JA in Cd stress.
基金financially supported by the National Transgenic Plant Research Program of China(2016ZX08005-001)the Program of Introducing Talents of Discipline to Universities in China(B14032)+1 种基金the open funds of the National Key Laboratory of Crop Genetic Improvement(ZK201901)the National Natural Science Foundation of China(31771837)。
文摘Cotton fibers are single cells originating in the epidermis of cotton ovules,and serve as the largest natural fiber source for the textile industry.In theory,all epidermal cells have the potential to develop into fibers,but only 15%–25%of epidermis cells develop into commercially viable lint fibers.We previously showed that Gh Lac1 participates in cotton defense against biotic stress.Here we report that Gh Lac1 also has a role in cotton fiber development.Gh Lac1 RNAi lines in cotton showed increased differentiation of fiber initials from epidermis and shortened fiber length,resulting in unchanged lint percentage.Suppression of Gh Lac1 expression led to constitutively hyperaccumulated jasmonic acid(JA)and flavonoids in ovules and fiber cells.In vitro ovule culture experiments confirmed the distinct roles of JA and flavonoids in fiber initiation and elongation,and showed that fiber development is spatially regulated by these chemicals:the increased fiber initiation in Gh Lac1 RNAi lines is caused by hyperaccumulated JA and rutin content during the fiber initiation stage and shortened fiber length is caused by constitutively increased JA and naringenin content during the fiber elongation stage.
文摘Jasmonates are class of plant growth regulators act as signal molecule that intercede various components in physiological and metabolic regulation, stress responses and possibly communication through signal transduction. Oxidative stress due to heavy metal exposure stimulates synthesis and activity of antioxidant metabolites and enhances antioxidant enzyme activities that could protect plant tissues. The aim of this study was to investigate the exogenous effect of JA at seed level which can transduce throughout seedling growth and regulate antioxidant activities such as superoxide dismutase (SOD;EC 1.15.1.1) and guaiacol peroxidase (POD;EC 1.11.1.7) in 12 days old seedlings of pigeon pea (Cajanus cajan (L.) Millsp.) in presence and/or absence of copper. The activity of SOD and POD increased significantly in presence of Cu2+ after seed priming with JA. JA also helps in chlorophyll and carotenoid accumulation and neutralizes the toxic effect of Cu2+ on seedlings. This is the first report of JA effect on photosynthetic pigment accumulation and H2O2 mitigating enzymes i.e. SOD and POD and it could be recommended that seed priming with JA help in ameliorating toxic effect of Cu2+.
基金funding support from the National Natural Science Foundation of China (32072024)the Fundamental Research Funds for the Central Universities (2021ZKPY019)the National Key Research and Development Program of China (2018YFD0100403, 2016YFD0101402)。
文摘Cotton(Gossypium spp.) yield is reduced by stress. In this study, high temperature(HT) suppressed the expression of the jasmonic acid(JA) biosynthesis gene allene oxide cyclase 2(GhAOC2), reducing JA content and causing male sterility in the cotton HT-sensitive line H05. Anther sterility was reversed by exogenous application of methyl jasmonate(MeJA) to early buds. To elucidate the role of GhAOC2 in JA biosynthesis and identify its putative contribution to the anther response to HT, we created gene knockout cotton plants using the CRISPR/Cas9 system. Ghaoc2 mutant lines showed male-sterile flowers with reduced JA content in the anthers at the tetrad stage(TS), tapetum degradation stage(TDS), and anther dehiscence stage(ADS). Exogenous application of MeJA to early mutant buds(containing TS or TDS anthers) rescued the sterile pollen and indehiscent anther phenotypes, while ROS signals were reduced in ADS anthers. We propose that HT downregulates the expression of GhAOC2 in anthers, reducing JA biosynthesis and causing excessive ROS accumulation in anthers, leading to male sterility. These findings suggest exogenous JA application as a strategy for increasing male fertility in cotton under HT.
基金Supported by the Innovation Fund for Undergraduate of Jilin University(2016A82361)~~
文摘To explore the regulatory effects of jasmonic acid （JA） on the expression of the genes involved in capsaicin biosynthesis pathway, the mRNA expression of the genes was determined by fluorescence-based quantitative PCR 0, 4, 12, 24 and 48 h after chili peppers （Capsicum annuum var. conoides） were treated with 100 μmol/L JA, and the content of capsaicin was measured by high performance liquid chromatography （HPLC） 0, 1, 3, 6, 10 and 15 d after JA treatment. The results showed that JA upregulated the mRNA levels of pal, C4h, Comt, 4Cl, Hct, Paint, Bcat, FatA and pun1 in chili pepper, thus promoting the synthesis of capsaicin to different extents.
基金funded by the National Key Research and Development Program of China (2021YFF1000302,2022YFF1003500, and 2022YFF1002400)the Fundamental Research Funds for the Central Universities of China (FRF-IDRY-20-038 and 06500136)the National Natural Science Foundation of China (31971958)。
文摘Plant male reproduction is a fine-tuned developmental process that is susceptible to stressful environments and influences crop grain yields.Phytohormone signaling functions in control of plant normal growth and development as well as in response to external stresses,but the interaction or crosstalk among phytohormone signaling,stress response,and male reproduction in plants remains poorly understood.Cross-species comparison among 514 stress-response transcriptomic libraries revealed that ms33-6038,a genic male sterile mutant deficient in the Zm Ms33/Zm GPAT6 gene,displayed an excessive drought stress-like transcriptional reprogramming in anthers triggered mainly by disturbed jasmonic acid(JA)homeostasis.An increased level of JA appeared in Zm Ms33-deficient anthers at both meiotic and postmeiotic stages and activated genes involved in JA biosynthesis and signaling as well as genes functioning in JA-mediated drought response.Excessive accumulation of JA elevated expression level of a gene encoding a WRKY transcription factor that activated the Zm Ms33 promoter.These findings reveal a feedback loop of Zm Ms33-JA-WRKY-Zm Ms33 in controlling male sterility and JA-mediated stress response in maize,shedding light on the crosstalk of stress response and male sterility mediated by phytohormone homeostasis and signaling.
