Glutaredoxins （GRXs） are ubiquitous oxidoreductases that play a crucial role in response to oxidative stress by reducing disulfides in various organisms. In planta, three different GRX classes have been identified a...Glutaredoxins （GRXs） are ubiquitous oxidoreductases that play a crucial role in response to oxidative stress by reducing disulfides in various organisms. In planta, three different GRX classes have been identified according to their active site motifs. CPYC and CGFS classes are found in all organisms, whereas the CC-type class is specific for higher land plants. Recently, two Arabidopsis CC-type GRXs, ROXY1 and ROXY2, were shown to exert crucial functions in petal and anther initiation and differentiation. To analyze the function of CC-type GRXs in the distantly related monocots, we isolated and characterized OsROXY1 and OsROXY2-two rice homologs of ROXY1. Both genes are expressed in vegetative and reproductive stages. Although rice flower morphology is distinct from eudicots, OsROXY1/2 floral expression patterns are similar to their Arabidopsis counterparts ROXY1/2. Complementation experiments demonstrate that OsROXY1 and OsROXY2 can fully rescue the roxyl floral mutant phenotype. Overexpression of OsROXY1, OsROXY2, and ROXY1 in Arabidopsis causes similar vegetative and reproductive plant developmental defects. ROXY1 and its rice homologs thus exert a conserved function during eudicot and monocot flower development. Strikingly, overexpression of these CC-type GRXs also leads to an increased accumulation of hydrogen peroxide levels and hyper-susceptibility to infection from the necrotrophic pathogen Botrytis cinerea, revealing the importance of balanced redox processes in flower organ develop- ment and pathogen defence.展开更多
Excessive N-acetyl-p-benzoquinone imine(NAPQI)formation is a starting event that triggers oxidative stress and subsequent hepatocyte necrosis in acetaminophen(APAP)overdose caused acute liver failure(ALF).S-glutathion...Excessive N-acetyl-p-benzoquinone imine(NAPQI)formation is a starting event that triggers oxidative stress and subsequent hepatocyte necrosis in acetaminophen(APAP)overdose caused acute liver failure(ALF).S-glutathionylation is a reversible redox post-translational modification and a prospective mechanism of APAP hepatotoxicity.Glutaredoxin-1(Glrx1),a glutathione-specific thioltransferase,is a primary enzyme to catalyze deglutathionylation.The objective of this study was to explored whether and how Glrx1 is associated with the development of ALF induced by APAP.The Glrx1 knockout mice(Glrx1^(-/-))and liver-specific overexpression of Glrx1(AAV8-Glrx1)mice were produced and underwent APAPinduced ALF.Pirfenidone(PFD),a potential inducer of Glrx1,was administrated preceding APAP to assess its protective effects.Our results revealed that the hepatic total protein S-glutathionylation(PSSG)increased and the Glrx1 level reduced in mice after APAP toxicity.Glrx1^(-/-)mice were more sensitive to APAP overdose,with higher oxidative stress and more toxic metabolites of APAP.This was attributed to Glrx1 deficiency increasing the total hepatic PSSG and the S-glutathionylation of cytochrome p4503a11(Cyp3a11),which likely increased the activity of Cyp3a11.Conversely,AAV8-Glrx1 mice were defended against liver damage caused by APAP overdose by inhibiting the S-glutathionylation and activity of Cyp3a11,which reduced the toxic metabolites of APAP and oxidative stress.PFD precede administration upregulated Glrx1 expression and alleviated APAP-induced ALF by decreasing oxidative stress.We have identified the function of Glrx1 mediated PSSG in liver injury caused by APAP overdose.Increasing Glrx1 expression may be investigated for the medical treatment of APAP-caused hepatic injury.展开更多
Cytoskeletal proteins are susceptible to glutathionylation under oxidizing conditions,and oxidative damage has been implicated in several neurodegenerative diseases.End-binding protein 1(EB1)is a master regulator of m...Cytoskeletal proteins are susceptible to glutathionylation under oxidizing conditions,and oxidative damage has been implicated in several neurodegenerative diseases.End-binding protein 1(EB1)is a master regulator of microtubule plus-end tracking proteins(+TIPs)and is critically involved in the control of microtubule dynamics and cellular processes.However,the impact of glutathionylation on EB1 functions remains unknown.Here we reveal that glutathionylation is important for controlling EB1 activity and protecting EB1 from irreversible oxidation.In vitro biochemical and cellular assays reveal that EB1 is glutathionylated.Diamide,a mild oxidizing reagent,reduces EB1 comet number and length in cells,indicating the impairment of microtubule dynamics.Three cysteine residues of EB1 are glutathionylated,with mutations of these three cysteines to serines attenuating microtubule dynamics but buffering diamide-induced decrease in microtubule dynamics.In addition,glutaredoxin 1(Grx1)deglutathionylates EB1,and Grx1 depletion suppresses microtubule dynamics and leads to defects in cell division orientation and cell migration,suggesting a critical role of Grx1-mediated deglutathionylation in maintaining EB1 activity.Collectively,these data reveal that EB1 glutathionylation is an important protective mechanism for the regulation of microtubule dynamics and microtubule-based cellular activities.展开更多
目的:观察谷氧还蛋白1(glutaredoxin1,Grx1)在高糖诱导的血管内皮细胞凋亡中的作用及机制.方法:在高糖环境中培养人脐静脉内皮细胞,制备人脐静脉内皮细胞损伤模型.细胞分为正常对照组、损伤组、Grx1预保护组.倒置显微镜下观察细胞形态....目的:观察谷氧还蛋白1(glutaredoxin1,Grx1)在高糖诱导的血管内皮细胞凋亡中的作用及机制.方法:在高糖环境中培养人脐静脉内皮细胞,制备人脐静脉内皮细胞损伤模型.细胞分为正常对照组、损伤组、Grx1预保护组.倒置显微镜下观察细胞形态.MTT比色法检测细胞活力以初步观察Grx1对细胞损伤的作用;采用Annexin VFITC/PI双染法,流式细胞仪检测Grx1对人脐静脉内皮细胞凋亡的影响;利用Western blot法分析Grx1对Akt、JNK蛋白水平表达的影响.结果:Grx1预保护组与损伤组比较,细胞状态明显改善.与高糖损伤组比较,Grx1预保护组的细胞存活率显著提高(78%±3% vs 59%±2%,P<0.05),早期凋亡率(0.2360%±0.0156% vs 0.4156%±0.0374%,P<0.05)和晚期凋亡率(0.2433%±0.0278% vs 0.3689%±0.0083%,P<0.05)均明显降低.与正常对照组相比,高糖组p-JNK相对含量明显增多(0.64±0.07 vs 0.48±0.03,P<0.05),而高糖组p-Akt水平较正常对照组显著降低(1.29±0.035 vs 0.69±0.11,P<0.01).同时,hGrx1保护后p-JNK蛋白水平较高糖组显著降低(0.39±0.05 vs 0.64±0.07,P<0.05);而p-Akt蛋白水平较高糖组显著增高(0.69±0.11 vs 1.07±0.13,P<0.01).结论:Grx1可通过抑制JNK激活及激活Akt通路来拮抗高糖诱导的内皮细胞凋亡.展开更多
文摘Glutaredoxins （GRXs） are ubiquitous oxidoreductases that play a crucial role in response to oxidative stress by reducing disulfides in various organisms. In planta, three different GRX classes have been identified according to their active site motifs. CPYC and CGFS classes are found in all organisms, whereas the CC-type class is specific for higher land plants. Recently, two Arabidopsis CC-type GRXs, ROXY1 and ROXY2, were shown to exert crucial functions in petal and anther initiation and differentiation. To analyze the function of CC-type GRXs in the distantly related monocots, we isolated and characterized OsROXY1 and OsROXY2-two rice homologs of ROXY1. Both genes are expressed in vegetative and reproductive stages. Although rice flower morphology is distinct from eudicots, OsROXY1/2 floral expression patterns are similar to their Arabidopsis counterparts ROXY1/2. Complementation experiments demonstrate that OsROXY1 and OsROXY2 can fully rescue the roxyl floral mutant phenotype. Overexpression of OsROXY1, OsROXY2, and ROXY1 in Arabidopsis causes similar vegetative and reproductive plant developmental defects. ROXY1 and its rice homologs thus exert a conserved function during eudicot and monocot flower development. Strikingly, overexpression of these CC-type GRXs also leads to an increased accumulation of hydrogen peroxide levels and hyper-susceptibility to infection from the necrotrophic pathogen Botrytis cinerea, revealing the importance of balanced redox processes in flower organ develop- ment and pathogen defence.
基金Supported by Postdoctoral Researcher of Heilongjiang Postdoctoral Management Office(No.LBH-Q16225)Qiqihar Medical University(No.QY2016LX-01 and QY2016B-36)~~
基金supported by the National Natural Science Foundation of China(Grant Nos.:82025007,81930020,and 82170874)China Postdoctoral Science Foundation(Grant No.:2022M710099).
文摘Excessive N-acetyl-p-benzoquinone imine(NAPQI)formation is a starting event that triggers oxidative stress and subsequent hepatocyte necrosis in acetaminophen(APAP)overdose caused acute liver failure(ALF).S-glutathionylation is a reversible redox post-translational modification and a prospective mechanism of APAP hepatotoxicity.Glutaredoxin-1(Glrx1),a glutathione-specific thioltransferase,is a primary enzyme to catalyze deglutathionylation.The objective of this study was to explored whether and how Glrx1 is associated with the development of ALF induced by APAP.The Glrx1 knockout mice(Glrx1^(-/-))and liver-specific overexpression of Glrx1(AAV8-Glrx1)mice were produced and underwent APAPinduced ALF.Pirfenidone(PFD),a potential inducer of Glrx1,was administrated preceding APAP to assess its protective effects.Our results revealed that the hepatic total protein S-glutathionylation(PSSG)increased and the Glrx1 level reduced in mice after APAP toxicity.Glrx1^(-/-)mice were more sensitive to APAP overdose,with higher oxidative stress and more toxic metabolites of APAP.This was attributed to Glrx1 deficiency increasing the total hepatic PSSG and the S-glutathionylation of cytochrome p4503a11(Cyp3a11),which likely increased the activity of Cyp3a11.Conversely,AAV8-Glrx1 mice were defended against liver damage caused by APAP overdose by inhibiting the S-glutathionylation and activity of Cyp3a11,which reduced the toxic metabolites of APAP and oxidative stress.PFD precede administration upregulated Glrx1 expression and alleviated APAP-induced ALF by decreasing oxidative stress.We have identified the function of Glrx1 mediated PSSG in liver injury caused by APAP overdose.Increasing Glrx1 expression may be investigated for the medical treatment of APAP-caused hepatic injury.
基金supported by the National Natural Science Foundation of China(31701216,31771542,31900502)the Natural Science Foundation of Shandong Province(ZR2017MC008)。
文摘Cytoskeletal proteins are susceptible to glutathionylation under oxidizing conditions,and oxidative damage has been implicated in several neurodegenerative diseases.End-binding protein 1(EB1)is a master regulator of microtubule plus-end tracking proteins(+TIPs)and is critically involved in the control of microtubule dynamics and cellular processes.However,the impact of glutathionylation on EB1 functions remains unknown.Here we reveal that glutathionylation is important for controlling EB1 activity and protecting EB1 from irreversible oxidation.In vitro biochemical and cellular assays reveal that EB1 is glutathionylated.Diamide,a mild oxidizing reagent,reduces EB1 comet number and length in cells,indicating the impairment of microtubule dynamics.Three cysteine residues of EB1 are glutathionylated,with mutations of these three cysteines to serines attenuating microtubule dynamics but buffering diamide-induced decrease in microtubule dynamics.In addition,glutaredoxin 1(Grx1)deglutathionylates EB1,and Grx1 depletion suppresses microtubule dynamics and leads to defects in cell division orientation and cell migration,suggesting a critical role of Grx1-mediated deglutathionylation in maintaining EB1 activity.Collectively,these data reveal that EB1 glutathionylation is an important protective mechanism for the regulation of microtubule dynamics and microtubule-based cellular activities.
文摘目的:观察谷氧还蛋白1(glutaredoxin1,Grx1)在高糖诱导的血管内皮细胞凋亡中的作用及机制.方法:在高糖环境中培养人脐静脉内皮细胞,制备人脐静脉内皮细胞损伤模型.细胞分为正常对照组、损伤组、Grx1预保护组.倒置显微镜下观察细胞形态.MTT比色法检测细胞活力以初步观察Grx1对细胞损伤的作用;采用Annexin VFITC/PI双染法,流式细胞仪检测Grx1对人脐静脉内皮细胞凋亡的影响;利用Western blot法分析Grx1对Akt、JNK蛋白水平表达的影响.结果:Grx1预保护组与损伤组比较,细胞状态明显改善.与高糖损伤组比较,Grx1预保护组的细胞存活率显著提高(78%±3% vs 59%±2%,P<0.05),早期凋亡率(0.2360%±0.0156% vs 0.4156%±0.0374%,P<0.05)和晚期凋亡率(0.2433%±0.0278% vs 0.3689%±0.0083%,P<0.05)均明显降低.与正常对照组相比,高糖组p-JNK相对含量明显增多(0.64±0.07 vs 0.48±0.03,P<0.05),而高糖组p-Akt水平较正常对照组显著降低(1.29±0.035 vs 0.69±0.11,P<0.01).同时,hGrx1保护后p-JNK蛋白水平较高糖组显著降低(0.39±0.05 vs 0.64±0.07,P<0.05);而p-Akt蛋白水平较高糖组显著增高(0.69±0.11 vs 1.07±0.13,P<0.01).结论:Grx1可通过抑制JNK激活及激活Akt通路来拮抗高糖诱导的内皮细胞凋亡.
