Mitogen-activated protein kinase(MAPK)cascades are key signaling modules downstream of receptors/sensors that perceive either endogenously produced stimuli such as peptide ligands and damage-associated molecular patte...Mitogen-activated protein kinase(MAPK)cascades are key signaling modules downstream of receptors/sensors that perceive either endogenously produced stimuli such as peptide ligands and damage-associated molecular patterns(DAMPs)or exogenously originated stimuli such as pathogen/microbe-associated molecular patterns(P/MAMPs),pathogen-derived effectors,and environmental factors.In this review,we provide a historic view of plant MAPK research and summarize recent advances in the establishment of MAPK cascades as essential components in plant immunity,response to environmental stresses,and normal growth and development.Each tier of the MAPK cascades is encoded by a small gene family,and multi ple members can function redundantly in an MAPK cascade.Yet,they carry out a diverse array of biological functions in plants.How the signaling specificity is achieved has become an interesting topic of MAPK research.Future investigations into the molecular mechanism(s)underlying the regulation of MAPK activation including the activation kinetics and magnitude in response to a stimulus,the spatiotemporal expression patterns of all the components in the signaling pathway,and functional characterization of novel MAPK substrates are central to our understanding of MAPK functions and signaling specificity in plants.展开更多
OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric an...OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P展开更多
The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi. The agbl mutant impaired in the Gβ subunit displays enhanced susceptibility to these pathogens. Gβ/AGB1 forms a...The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi. The agbl mutant impaired in the Gβ subunit displays enhanced susceptibility to these pathogens. Gβ/AGB1 forms an obligate dimer with either one of the Arabidopsis Gγsubunits （γ1/AGG1 and γ2/AGG2）. Accordingly, we now demonstrate that the aggl agg2 double mutant is as susceptible as agbl plants to the necrotrophic fungus Plectosphaerella cucumerina. To elucidate the molecular basis of heterotrimeric G-protein-mediated resistance, we performed a comparative transcriptomic analysis of agbl-1 mutant and wild-type plants upon inoculation with P cucumerina. This analysis, together with metab- olomic studies, demonstrated that G-protein-mediated resistance was independent of defensive pathways required for resistance to necrotrophic fungi, such as the salicylic acid, jasmonic acid, ethylene, abscisic acid, and tryptophan-derived metabolites signaling, as these pathways were not impaired in agbl and aggl agg2 mutants. Notably, many mis-reguiated genes in agbl plants were related with cell wall functions, which was also the case in aggl agg2 mutant. Biochemical analyses and Fourier Transform InfraRed （FTIR） spectroscopy of cell walls from G-protein mutants revealed that the xylose content was lower in agbl and aggl agg2 mutants than in wild-type plants, and that mutant walls had similar FTIR spec-tratypes, which differed from that of wild-type plants. The data presented here suggest a canonical functionality of the Gβ and Gγ1/γ2 subunits in the control of Arabidopsis immune responses and the regulation of cell wall composition.展开更多
As sessile organisms, plants are exposed to pathogen invasions and environmental fluctuations. To overcome the challenges of their surroundings, plants acquire the potential to sense endogenous and exogenous cues, res...As sessile organisms, plants are exposed to pathogen invasions and environmental fluctuations. To overcome the challenges of their surroundings, plants acquire the potential to sense endogenous and exogenous cues, resulting in their adaptability. Hence, plants have evolved a large collection of plasma membrane-resident receptors, including RECEPTOR-LIKE KINASEs(RLKs) and RECEPTOR-LIKE PROTEINs(RLPs) to perceive those signals and regulate plant growth,development, and immunity. The ability of RLKs and RLPs to recognize distinct ligands relies on diverse categories of extracellular domains evolved. Co-regulatory receptors are often required to associate with RLKs and RLPs to facilitate cellular signal transduction. RECEPTOR-LIKE CYTOPLASMIC KINASEs(RLCKs) also associate with the complex, bifurcating the signal to key signaling hubs, such as MITOGEN-ACTIVATED PROTEIN KINASE(MAPK) cascades, to regulate diverse biological processes. Here, we discuss recent knowledge advances in understanding the roles of RLKs and RLPs in plant growth, development, and immunity, and their connection with co-regulatory receptors, leading to activation of diverse intracellular signaling pathways.展开更多
Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In th...Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In this study,we demonstrate that flg22 priming attenuates Pseudomonas syringae pv.tomato DC3000(Pst)AvrRpt2-induced hypersensitive cell death,resistance,and biomass reduction in Arabidopsis.Mitogen-activated protein kinases(MAPKs)are key signaling regulators of PTI and ETI.The absence of MPK3 and MPK6 significantly reduces pre-PTI-mediated ETI suppression(PES).We found that MPK3/MPK6 interact with and phosphorylate the downstream transcription factor WRKY18,which regulates the expression of AP2C1 and PP2C5,two genes encoding protein phosphatases.Furthermore,we observed that the PTI-suppressed ETI-triggered cell death,MAPK activation,and growth retardation are significantly attenuated in wrky18/40/60 and ap2c1 pp2c5 mutants.Taken together,our results suggest that the MPK3/MPK6-WRKYs-PP2Cs module underlies PES and is essential for the maintenance of plant fitness during ETI.展开更多
基金supported by the Zhongshan Young Principal Investigator award from Nanjing Agricultural University and a grant from Jiangsu Provincial Post-doctoral Research Funding Program(2020Z325)。
文摘Mitogen-activated protein kinase(MAPK)cascades are key signaling modules downstream of receptors/sensors that perceive either endogenously produced stimuli such as peptide ligands and damage-associated molecular patterns(DAMPs)or exogenously originated stimuli such as pathogen/microbe-associated molecular patterns(P/MAMPs),pathogen-derived effectors,and environmental factors.In this review,we provide a historic view of plant MAPK research and summarize recent advances in the establishment of MAPK cascades as essential components in plant immunity,response to environmental stresses,and normal growth and development.Each tier of the MAPK cascades is encoded by a small gene family,and multi ple members can function redundantly in an MAPK cascade.Yet,they carry out a diverse array of biological functions in plants.How the signaling specificity is achieved has become an interesting topic of MAPK research.Future investigations into the molecular mechanism(s)underlying the regulation of MAPK activation including the activation kinetics and magnitude in response to a stimulus,the spatiotemporal expression patterns of all the components in the signaling pathway,and functional characterization of novel MAPK substrates are central to our understanding of MAPK functions and signaling specificity in plants.
文摘OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P
文摘The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi. The agbl mutant impaired in the Gβ subunit displays enhanced susceptibility to these pathogens. Gβ/AGB1 forms an obligate dimer with either one of the Arabidopsis Gγsubunits （γ1/AGG1 and γ2/AGG2）. Accordingly, we now demonstrate that the aggl agg2 double mutant is as susceptible as agbl plants to the necrotrophic fungus Plectosphaerella cucumerina. To elucidate the molecular basis of heterotrimeric G-protein-mediated resistance, we performed a comparative transcriptomic analysis of agbl-1 mutant and wild-type plants upon inoculation with P cucumerina. This analysis, together with metab- olomic studies, demonstrated that G-protein-mediated resistance was independent of defensive pathways required for resistance to necrotrophic fungi, such as the salicylic acid, jasmonic acid, ethylene, abscisic acid, and tryptophan-derived metabolites signaling, as these pathways were not impaired in agbl and aggl agg2 mutants. Notably, many mis-reguiated genes in agbl plants were related with cell wall functions, which was also the case in aggl agg2 mutant. Biochemical analyses and Fourier Transform InfraRed （FTIR） spectroscopy of cell walls from G-protein mutants revealed that the xylose content was lower in agbl and aggl agg2 mutants than in wild-type plants, and that mutant walls had similar FTIR spec-tratypes, which differed from that of wild-type plants. The data presented here suggest a canonical functionality of the Gβ and Gγ1/γ2 subunits in the control of Arabidopsis immune responses and the regulation of cell wall composition.
基金supported by the Brazilian National Council for Scientific and Technological Development (CNPq) (201710/2014-5) to A.M.E.A.MPEW Latin American Fellows Program to F.A.O.-M.+3 种基金National Institutes of Health (NIH) (R01GM092893)National Science Foundation (NSF) (MCB-1906060) to P.H.NIH (R01GM097247)the Robert A. Welch Foundation (A-1795) to L.S.
文摘As sessile organisms, plants are exposed to pathogen invasions and environmental fluctuations. To overcome the challenges of their surroundings, plants acquire the potential to sense endogenous and exogenous cues, resulting in their adaptability. Hence, plants have evolved a large collection of plasma membrane-resident receptors, including RECEPTOR-LIKE KINASEs(RLKs) and RECEPTOR-LIKE PROTEINs(RLPs) to perceive those signals and regulate plant growth,development, and immunity. The ability of RLKs and RLPs to recognize distinct ligands relies on diverse categories of extracellular domains evolved. Co-regulatory receptors are often required to associate with RLKs and RLPs to facilitate cellular signal transduction. RECEPTOR-LIKE CYTOPLASMIC KINASEs(RLCKs) also associate with the complex, bifurcating the signal to key signaling hubs, such as MITOGEN-ACTIVATED PROTEIN KINASE(MAPK) cascades, to regulate diverse biological processes. Here, we discuss recent knowledge advances in understanding the roles of RLKs and RLPs in plant growth, development, and immunity, and their connection with co-regulatory receptors, leading to activation of diverse intracellular signaling pathways.
基金supported by grants from the National Key Research and Development Project(2022YFE0198100)National Natural Science Foundation of China(32172420)+2 种基金Natural Science Foundation of Jiangsu Province(SBK20220085)Fundamental Research Funds for the Central Universities(KYXK202009,ZJ21195012)the Startup Fund for Distinguished Scholars from Nanjing Agricultural University(to Y.W.).
文摘Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In this study,we demonstrate that flg22 priming attenuates Pseudomonas syringae pv.tomato DC3000(Pst)AvrRpt2-induced hypersensitive cell death,resistance,and biomass reduction in Arabidopsis.Mitogen-activated protein kinases(MAPKs)are key signaling regulators of PTI and ETI.The absence of MPK3 and MPK6 significantly reduces pre-PTI-mediated ETI suppression(PES).We found that MPK3/MPK6 interact with and phosphorylate the downstream transcription factor WRKY18,which regulates the expression of AP2C1 and PP2C5,two genes encoding protein phosphatases.Furthermore,we observed that the PTI-suppressed ETI-triggered cell death,MAPK activation,and growth retardation are significantly attenuated in wrky18/40/60 and ap2c1 pp2c5 mutants.Taken together,our results suggest that the MPK3/MPK6-WRKYs-PP2Cs module underlies PES and is essential for the maintenance of plant fitness during ETI.
