Transglutaminases(TGases)are multifunctional enzymes involved in stress responses,while autophagy is a key cellular degradation process.However,the relationship between TGases and autophagy in the plant heat stress re...Transglutaminases(TGases)are multifunctional enzymes involved in stress responses,while autophagy is a key cellular degradation process.However,the relationship between TGases and autophagy in the plant heat stress response remains poorly understood.In this study,we demonstrated that TGase was essential for heat tolerance by regulating autophagy.Heat stress induced both TGase expression and activity.The tgase mutants reduced,while TGase-overexpression(TGaseOE)lines increased plant thermotolerance.Under heat stress,insoluble proteins were more ubiquitinated in tgase mutants and less so in TGaseOE plants.Moreover,TGase promoted the expression of autophagy-related(ATG)genes and autophagosome formation.Polyamine content and the expression of polyamine-related genes,particularly SAMS2,were positively correlated with TGase activity.TGase interacted with SAMS2 both in vitro and in vivo,and knockout of SAMS2 impaired TGase-induced thermotolerance and autophagosome formation in TGaseOE plants.Exogenous spermidine also promoted autophagosome formation in tgase mutants,indicating a critical role of polyamine in TGase-mediated heat tolerance and autophagosome formation.Furthermore,a cell-free degradation assay showed that TGase enhanced the stability of SAMS2.Altogether,these results reveal that TGase interacts with and stabilizes SAMS2 to promote polyamine synthesis,which upregulates ATG gene expression and facilitates autophagosome formation to degrade ubiquitinated proteins,thereby enhancing the thermotolerance of tomato plants.展开更多
demonstrated to hydrogenate dangling bonds on the surface of crystalline silicon(c-Si),which reduces the interface defect density,thus enabling an outstanding passivation effect[1–3].However,like many other industria...demonstrated to hydrogenate dangling bonds on the surface of crystalline silicon(c-Si),which reduces the interface defect density,thus enabling an outstanding passivation effect[1–3].However,like many other industrial c-Si solar cells that suffer from light-induced degradation and light and elevated temperature induced degradation(LeTID)[4,5],the decay of electrical properties has also been found in thin-film a-Si:H solar cells[6–8],as well as samples of c-Si coated with intrinsic a-Si:H films after light soaking[9].A significant observation reported by Plagwitz et al.[10]suggested that illumination induced an increase in surface recombination velocities for both a-Si:H coated p-type and n-type c-Si substrates.The degradation of performance is generally attributed to the generation of deeplevel defects acting as recombination centers,most likely as single dangling bonds[11,12],which is considered to be related to the Staebler-Wronski effect(SWE)[13].展开更多
Thrombosis,secondary to rupture of unstable plaque,is a fatal risk factor for myocardial infarction and ischemic stroke.At present,more novel methods are needed for the diagnosis and treatment of vulnerable plaque.Her...Thrombosis,secondary to rupture of unstable plaque,is a fatal risk factor for myocardial infarction and ischemic stroke.At present,more novel methods are needed for the diagnosis and treatment of vulnerable plaque.Here,we report a hollow polydopamine/Zn(HPDA/Zn)ultrasound contrast agent.Through western-blot,Elisa,and other experiments,we found that in addition to having a good contrast-enhancement capability in ultrasound imaging in vitro and in vivo,HPDA/Zn also has the effect of reducing the expres-sion of CREB.CREB protein and its downstream-regulated proteins and factors are closely related to the stability of plaque.HPDA/Zn has the effect of reducing the expression of CREB protein,which leads to the decrease of expression of MMP-9,the regulatory pro-tein downstream of the CREB protein.In addition,it also reduces the secretion of inflammatory factors hs-CRP and IL-17A.Thus,HPDA/Zn can stabilize plaque by inhibiting CREB and reducing plaque vulnerable markers and inflammatory factors.In a word,HPDA/Zn is a kind of ultrasound contrast agent,which can stabilize plaques by inhibiting CREB protein.展开更多
Background Se(selenium)pollution is an emerging environmental concern.Excessive Se induces phytotoxicity.The endogenous H2S(hydrogen sulfide)was involved in plant adaptation to Se stress,but the signaling player of H2...Background Se(selenium)pollution is an emerging environmental concern.Excessive Se induces phytotoxicity.The endogenous H2S(hydrogen sulfide)was involved in plant adaptation to Se stress,but the signaling player of H2S remains unclear.Methods The study was conducted in a hydroponic system with different chemicals added to the treatment solution.Fluorescent tracking was performed to detect endogenous signaling molecules in plant tissues.Physiological changes were determined based on pharmaceutics and histochemical experiments.Gene expression was analyzed using qRT-PCR.The data were summarized using hierarchical cluster and Pearson correlation analysis.Results Se stress inhibited B.rapa growth(e.g.root elongation,shoot height,and seedling fresh weight and dry weight)in both dose-and time-dependent manners,with approximately 50%of root growth inhibition occurred at 20μM Se.Se stress induced ROS(reactive oxygen species)accumulation and oxidative injury in B.rapa.Se exposure resulted in the upregulation of LCDs(L-cysteine desulfhydrase)and DCDs(D-cysteine desulfhydrase)encoding enzymes for H2S production in B.rapa at early stage of Se exposure,followed by downregulation of these genes at late stage.This was consistent with the change of endogenous H2S in B.rapa.Enhancing endogenous H2S level with NaHS(H2S donor)stimulates endogenous Ca^(2+) in B.rapa upon Se exposure,accompanied the attenuation of growth inhibition,ROS accumulation,oxidative injury,and cell death.The beneficial effects of H2S on detoxifying Se were blocked by decreasing endogenous Ca^(2+) level with Ca^(2+) channel blocker or Ca^(2+) chelator.Finally,hierarchical cluster com-bined with correlation analysis revealed that Ca^(2+) might acted as downstream of H2S to confer Se tolerance in B.rapa.Conclusion Ca^(2+) was an important player of H2S in the regulation of plant physiological response upon Se stress.Such findings extend our knowledge of the mechanism for Se-induced phytotoxicity.展开更多
基金supported by the National Natural Science Foundation of China(32472719,32302640)the Fundamental Research Funds for the Central Universities(KJYQ2025024)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20242064)the Jiangsu Provincial Association for Science,and Technology Youth Science and Technology Talent Support Project(JSTJ-2023-003)the earmarked fund for China Agriculture Research System(CARS-23)A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Transglutaminases(TGases)are multifunctional enzymes involved in stress responses,while autophagy is a key cellular degradation process.However,the relationship between TGases and autophagy in the plant heat stress response remains poorly understood.In this study,we demonstrated that TGase was essential for heat tolerance by regulating autophagy.Heat stress induced both TGase expression and activity.The tgase mutants reduced,while TGase-overexpression(TGaseOE)lines increased plant thermotolerance.Under heat stress,insoluble proteins were more ubiquitinated in tgase mutants and less so in TGaseOE plants.Moreover,TGase promoted the expression of autophagy-related(ATG)genes and autophagosome formation.Polyamine content and the expression of polyamine-related genes,particularly SAMS2,were positively correlated with TGase activity.TGase interacted with SAMS2 both in vitro and in vivo,and knockout of SAMS2 impaired TGase-induced thermotolerance and autophagosome formation in TGaseOE plants.Exogenous spermidine also promoted autophagosome formation in tgase mutants,indicating a critical role of polyamine in TGase-mediated heat tolerance and autophagosome formation.Furthermore,a cell-free degradation assay showed that TGase enhanced the stability of SAMS2.Altogether,these results reveal that TGase interacts with and stabilizes SAMS2 to promote polyamine synthesis,which upregulates ATG gene expression and facilitates autophagosome formation to degrade ubiquitinated proteins,thereby enhancing the thermotolerance of tomato plants.
基金the National Natural Science Foundation of China(61974129,62025403,and 61721005)the Natural Science Foundation of Zhejiang Province(LD22E020001)Lingyan Research and Development Project of Zhejiang Province(022C01215).
文摘demonstrated to hydrogenate dangling bonds on the surface of crystalline silicon(c-Si),which reduces the interface defect density,thus enabling an outstanding passivation effect[1–3].However,like many other industrial c-Si solar cells that suffer from light-induced degradation and light and elevated temperature induced degradation(LeTID)[4,5],the decay of electrical properties has also been found in thin-film a-Si:H solar cells[6–8],as well as samples of c-Si coated with intrinsic a-Si:H films after light soaking[9].A significant observation reported by Plagwitz et al.[10]suggested that illumination induced an increase in surface recombination velocities for both a-Si:H coated p-type and n-type c-Si substrates.The degradation of performance is generally attributed to the generation of deeplevel defects acting as recombination centers,most likely as single dangling bonds[11,12],which is considered to be related to the Staebler-Wronski effect(SWE)[13].
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.81871411,32011530115,31971292 and 32101153)the Science&Technology Bureau of Ningbo City(Nos.2020z094,2021z072)+2 种基金the Natural Science Foundation of Ningbo(No.202003N4295)the Zhejiang Medical and Health Research Project Foundation(No.2023KY1138)the Excellent Member of Youth Innovation Promotion Association FoundationofCAS(Y2021079).
文摘Thrombosis,secondary to rupture of unstable plaque,is a fatal risk factor for myocardial infarction and ischemic stroke.At present,more novel methods are needed for the diagnosis and treatment of vulnerable plaque.Here,we report a hollow polydopamine/Zn(HPDA/Zn)ultrasound contrast agent.Through western-blot,Elisa,and other experiments,we found that in addition to having a good contrast-enhancement capability in ultrasound imaging in vitro and in vivo,HPDA/Zn also has the effect of reducing the expres-sion of CREB.CREB protein and its downstream-regulated proteins and factors are closely related to the stability of plaque.HPDA/Zn has the effect of reducing the expression of CREB protein,which leads to the decrease of expression of MMP-9,the regulatory pro-tein downstream of the CREB protein.In addition,it also reduces the secretion of inflammatory factors hs-CRP and IL-17A.Thus,HPDA/Zn can stabilize plaque by inhibiting CREB and reducing plaque vulnerable markers and inflammatory factors.In a word,HPDA/Zn is a kind of ultrasound contrast agent,which can stabilize plaques by inhibiting CREB protein.
基金funded by National Natural Science Foundation of China(32071968)China Agriculture Research System(CARS-23-B16)Jiangsu Agricultural Science and Technology Innovation Fund[CX(20)1011].
文摘Background Se(selenium)pollution is an emerging environmental concern.Excessive Se induces phytotoxicity.The endogenous H2S(hydrogen sulfide)was involved in plant adaptation to Se stress,but the signaling player of H2S remains unclear.Methods The study was conducted in a hydroponic system with different chemicals added to the treatment solution.Fluorescent tracking was performed to detect endogenous signaling molecules in plant tissues.Physiological changes were determined based on pharmaceutics and histochemical experiments.Gene expression was analyzed using qRT-PCR.The data were summarized using hierarchical cluster and Pearson correlation analysis.Results Se stress inhibited B.rapa growth(e.g.root elongation,shoot height,and seedling fresh weight and dry weight)in both dose-and time-dependent manners,with approximately 50%of root growth inhibition occurred at 20μM Se.Se stress induced ROS(reactive oxygen species)accumulation and oxidative injury in B.rapa.Se exposure resulted in the upregulation of LCDs(L-cysteine desulfhydrase)and DCDs(D-cysteine desulfhydrase)encoding enzymes for H2S production in B.rapa at early stage of Se exposure,followed by downregulation of these genes at late stage.This was consistent with the change of endogenous H2S in B.rapa.Enhancing endogenous H2S level with NaHS(H2S donor)stimulates endogenous Ca^(2+) in B.rapa upon Se exposure,accompanied the attenuation of growth inhibition,ROS accumulation,oxidative injury,and cell death.The beneficial effects of H2S on detoxifying Se were blocked by decreasing endogenous Ca^(2+) level with Ca^(2+) channel blocker or Ca^(2+) chelator.Finally,hierarchical cluster com-bined with correlation analysis revealed that Ca^(2+) might acted as downstream of H2S to confer Se tolerance in B.rapa.Conclusion Ca^(2+) was an important player of H2S in the regulation of plant physiological response upon Se stress.Such findings extend our knowledge of the mechanism for Se-induced phytotoxicity.
