The effects of cadmium stress on the growth, antioxidative enzymes and lipid peroxidation in two kenaf plants, Fuhong 991 and ZM412, were analysed under control (0.5-strength Hoagland's nutrient solution) or five l...The effects of cadmium stress on the growth, antioxidative enzymes and lipid peroxidation in two kenaf plants, Fuhong 991 and ZM412, were analysed under control (0.5-strength Hoagland's nutrient solution) or five levels of cadmium stress (0.5- strength Hoagland's nutrient solution containing different concentrations of Cd2+). The leaves and roots of control and cadmium-stressed plants were harvested after 3 wk. At the same Cd concentration, the Cd tolerance index of Fuhong 991 was higher than that of ZM412, indicating that Fuhong 991 may be more tolerant to Cd than ZM412. The superoxide dismutase (SOD), catalase activity (CAT) and peroxidase (POD) activities fluctuated in the leaves of the Cd-stressed plants compared to the control, whereas the glutathione reductase activity (GR) was much larger than the control for Fuhong 991, ensuring that sufficient quantities of GSH were available to respond to the cadmium stress. In comparison to the control, the dynamic tendency of the SOD, CAT and POD activities in roots of the Cd-stressed plants all increased and then declined, but the POD activity of Fuhong 991 remained nearly unchanged at all of the stress levels. The increase in the enzyme activities demonstrated that Fuhong 991 was more tolerant to cadmium than ZM 412. The lipid peroxidation was enhanced only in the leaves of Cd-stressed ZM 412. These findings indicated that antioxidative activities may play important roles in Cd-stressed Fuhong 991 and ZM 412 and that the leaf and root cell membranes of Fuhong 991 have a greater stability than those of ZM 412. For pollution monitoring purposes, the GR activity in the roots and leaves may serve as a biomarker of Cd for Fuhong 991, whereas lipid peroxidation may serve as biomarker for ZM 412.展开更多
A hydroponic culture experiment was done to investigate the effect of Cd stress on glutathione content (GSH) and glutathione S-transferase (GST, EC 2.5.1,18) activity in rice seedlings. The rice growth was severel...A hydroponic culture experiment was done to investigate the effect of Cd stress on glutathione content (GSH) and glutathione S-transferase (GST, EC 2.5.1,18) activity in rice seedlings. The rice growth was severely inhibited when Cd level in the solution was higher than 10 mg/L. In rice shoots, GSH content and GST activity increased with the increasing Cd level, while in roots, GST was obviously inhibited by Cd treatments, Compared with shoots, the rice roots had higher GSH content and GST activity, indicating the ability of Cd detoxification was much higher in roots than in shoots. There was a significant correlation between Cd level and GSH content or GST activity, suggesting that both parameters may be used as biomarkers of Cd stress in rice.展开更多
The B cells translocation gene 1 (BTG1) is a member of the BTG/TOB family of anti-proliferative genes, which have recently emerged as important regulators of cell growth and differentiation among vertebrates. Here, ...The B cells translocation gene 1 (BTG1) is a member of the BTG/TOB family of anti-proliferative genes, which have recently emerged as important regulators of cell growth and differentiation among vertebrates. Here, for the first time we cloned the full-length eDNA sequence of Hyriopsis schlegelii (Hs-BTG1), an economically important freshwater shellfish and potential indicator of environmental heavy metal pollution, for the first time. Using rapid amplification of eDNA ends (RACE) together with splicing the EST sequence from a haemocyte eDNA library, we found that Hs-BTG1 contains a 525 bp open reading frame (ORF) encoding a 174 amino-acid polypeptide, a 306 bp 5' untranslated region (5' UTR), and a 571 bp 3' UTR with a Poly(A) tail as well as a transcription termination signal (AATAAA). Homologne searching against GenBank revealed that Hs-BTG1 was closest to Crassostrea gigas BTG1, sharing 50.57% of protein identities. Hs-BTG1 also shares some typical features of the BTG/TOB family, possessing two well-conserved A and B boxes. Clustering analysis of Hs-BTG1 and other known BTGs showed that Hs-BTG1 was also closely related to BTG1 of C. gigas from the invertebrate BTG1 clade. Function prediction via homology modeling showed that both Hs-BTG1 and C. gigas BTG1 share a similar three-dimensional structure with Homo sapiens BTG1. Tissue-specific expression analysis of the Hs-BTG1 via real-time PCR showed that the transcripts were constitutively expressed, with the highest levels in the hepatopancreas and gills, and the lowest in both haemocyte and muscle tissue. Expression levels of Hs-BTG1 in hepatopancreas (2.03-fold), mantle (2.07-fold), kidney (2.2-fold) and haemocyte (2.5-fold) were enhanced by cadmium (Cd2+) stress, suggesting that Hs-BTG 1 may have played a significant role in H, schlegelii adaptation to adverse environmental conditions.展开更多
It is of great importance to solve the threats induced by cadmium pollution on crops. This paper examined the effect of biochar on cadmium accumulation in japonica rice and revealed the mechanism underlying the respon...It is of great importance to solve the threats induced by cadmium pollution on crops. This paper examined the effect of biochar on cadmium accumulation in japonica rice and revealed the mechanism underlying the response of protective enzyme system to cadmium stress. Biochar derived from rice straw was applied at two application rates under three cadmium concentrations. Shennong 265, super japonica rice variety, was selected as the test crop. The results indicated that cadmium content in above-ground biomass of rice increased with increasing soil cadmium concentrations, but the biochar application could suppress the accumulation of cadmium to some extent. Under high concentrations of cadmium, content of free proline and MDA (malondialdehyde) were high, so did the SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) activity in the flag leaf of rice. However, the protective enzyme activities remained at low level when biochar was added.展开更多
Melatonin(MLT)is a hormonal substance found in many organisms and can improve plant stress resistance.In this study,the japonica rice variety Y32 and indica rice variety NJ6 were cultivated in hydroponics under differ...Melatonin(MLT)is a hormonal substance found in many organisms and can improve plant stress resistance.In this study,the japonica rice variety Y32 and indica rice variety NJ6 were cultivated in hydroponics under different concentrations of CdCl2 at the two-leaf stage.The growth,physiological and biochemical responses of the seedlings and the expression of cadmium(Cd)-related genes under exogenous melatonin(MLT)treatment were assessed.The results indicated that Cd stress destroyed the dynamic balance between reactive oxygen species(ROS)production and removal,resulting in ROS accumulation,membrane lipid peroxidation,and impaired growth and development.Following the application of exogenous MLT to rice seedlings,increases in plant biomass including both underground and above-ground areas were observed.MLT also scavenged the inhibition of superoxide dismutase(SOD)and peroxidase(POD)in a concentration dependent manner in response to Cd stress.Catalase(CAT)activity and malondialdehyde(MDA)expression also decreased following MLT treatment.Amongst the six Cd-related genes assessed,five genes were downregulated and one was up-regulated in response to MLT treatment.Taken together,these data demonstrate that MLT improves the resilience of rice seedlings at the biochemical,physiological,and molecular levels,and diminishes the damage caused by Cd stress.展开更多
Cadmium (Cd) contamination in paddy soils poses a serious threat to the production and quality of rice. Among various biochemical processes related to Cd detoxification in rice, glutathione S-transferase (GST) pla...Cadmium (Cd) contamination in paddy soils poses a serious threat to the production and quality of rice. Among various biochemical processes related to Cd detoxification in rice, glutathione S-transferase (GST) plays an important role, catalyzing Cd complexation with glutathione (GSH) and scavenging reactive oxygen species (ROS) in cells. In this study, a hydroponic experiment was conducted to investigate the response of GST isozymes in rice roots upon Cd exposure. Results showed that the GST activity in rice roots was clearly enhanced by 50 pmol/L Cd treatment for 7 d. The GST isozymes were purified by ammonium sulphate precipitation, gel filtration chromatography and affinity chromatography. After being separated by SDS-PAGE and visualized by silver staining, GSTU6 was identified by in-gel digestion, MALDI-TOF-MS analysis and peptide mass fingerprint. The results confirm the vital function of tau class rice GST in Cd detoxification.展开更多
A proteomic approach including two-dimensional electrophoresis and mass spectrometric (MALDI-TOF MS) analyses was used to investigate the responses to cadmium (Cd) stress in seedlings of rice (Oryza sativa L.) v...A proteomic approach including two-dimensional electrophoresis and mass spectrometric (MALDI-TOF MS) analyses was used to investigate the responses to cadmium (Cd) stress in seedlings of rice (Oryza sativa L.) varieties Shanyou 63 and Aizaizhan. Cd stress significantly inhibited root and shoot growth, and affected the global proteome in rice roots and leaves, which induced or upregulated the expression of corresponding proteins in rice roots and leaves when rice seedlings were exposed to 0.1 or 1.0 mmol/L Cd. The Cd-induced proteins are involved in chelation and compartmentation of Cd, elimination of active oxygen free radicals, detoxification of toxic substances, degradation of denatured proteins or inactivated enzymes, regulation of physiologic metabolism and induction of pathogenesis-related proteins. Comparing the Cd-induced proteins between the two vadeties, the β-glucosidase and pathogenesis-related protein family 10 proteins were more drastically induced by Cd stress in roots and leaves of Aizaizhan, and the UDP-glucose protein transglucosylase and translational elongation factor Tu were induced by 0.1 mmol/L Cd stress in roots of Shanyou 63. This may be one of the important mechanisms for higher tolerance to Cd stress in Shanyou 63 than in Aizaizhan.展开更多
Toxic symptoms and tolerance mechanisms of heavy metal in maize are well documented. However, limited information is available regarding the changes in the proteome of maize seedling roots in response to cadmium(Cd) s...Toxic symptoms and tolerance mechanisms of heavy metal in maize are well documented. However, limited information is available regarding the changes in the proteome of maize seedling roots in response to cadmium(Cd) stress. Here, we employed an i TRAQ-based quantitative proteomic approach to characterize the dynamic alterations in the root proteome during early developmental in maize seedling. We conducted our proteomic experiments in three-day seedling subjected to Cd stress, using roots in four time points. We identified a total of 733, 307, 499, and 576 differentially abundant proteins after 12, 24, 48, or 72 h of treatment, respectively. These proteins displayed different functions, such as ribosomal synthesis, reactive oxygen species homeostasis, cell wall organization, cellular metabolism, and carbohydrate and energy metabolism. Of the 166 and 177 proteins with higher and lower abundance identified in at least two time points, 14 were common for three time points. We selected nine proteins to verify their expression using quantitative real-time PCR. Proteins involved in the ribosome pathway were especially responsive to Cd stress. Functional characterization of the proteins and the pathways identified in this study could help our understanding of the complicated molecular mechanism involved in Cd stress responses and create a list of candidate gene responsible for Cd tolerance in maize seeding roots.展开更多
The link between root growth, H2O2, auxin signaling, and the ceil cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) was analyzed in this study. Exposure to Cd induced a significant accumula...The link between root growth, H2O2, auxin signaling, and the ceil cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) was analyzed in this study. Exposure to Cd induced a significant accumulation of Cd, but caused a decrease in zinc (Zn) content which resulted from the decreased expression of OsHMA9 and OsZIP. Analysis using a Cd-specific probe showed that Cd was mainly localized in the meristematic zone and vascular tissues. Formation and elongation of the root system were significantly promoted by 3-amino-l,2,4-triazole (AT), but were markedly inhibited by N,N'. dimethylthiourea (DMTU) under Cd stress. The effect of H2O2 on Cd-stressed root growth was further confirmed by examining a gain-of-function rice mutant (carrying catalasel and glutathione-S-transferase) in the presence or absence of diphenylene iodonium. DR5-GUS staining revealed close associations between H2O2 and the concentration and distribution of auxin. H2O2 affected the expression of key genes, including OsYUCCA, OsPIN, OsARF, and OslAA, in the auxin signaling pathway in Cd-treated plants. These results suggest that H2O2 functions upstream of the auxin signaling pathway. Furthermore, H2O2 modified the expression of cell-cycle genes in Cd-treated roots. The effects of H2O2 on root system growth are therefore linked to auxin signal modification and to variations in the expression of cell-cycle genes in Cd-stressed rice. A working model for the effects of H2O2 on Cd-stressed root system growth is thus proposed and discussed in this paper.展开更多
Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-r...Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-responsive genes were induced by Cd treat- ment, and that their upregulation was suppressed in bhlh104 loss-of-function mutants, but enhanced upon overexpression of bHLH104. Correspondingly, the bhlh104 mutants displayed sensitivity to Cd stress, whereas plants overexpressing bHLH104 exhibited enhanced Cd tolerance. Further analysis suggested that bHLH104 positivelyregulates four heavy metal detoxification-associated genes, IREG2, A4TP3, HA4A3 and NAS4, which play roles in Cd sequestration and tolerance. The bHLH104 overexpres- sion plants accumulated high levels of Cd in the root but low levels of Cd in the shoot, which might contribute to the Cd tolerance in those lines. The present study thus points to bHLH104 as a potentially useful tool for genetic engineering of plants with enhanced Cd tolerance.展开更多
High concentrations of Cd can inhibit growth and reduce the activity of the photosynthetic apparatus in plants. In several plant species, aldo-keto reductases(AKRs) have been shown to enhance tolerance to various abio...High concentrations of Cd can inhibit growth and reduce the activity of the photosynthetic apparatus in plants. In several plant species, aldo-keto reductases(AKRs) have been shown to enhance tolerance to various abiotic stresses by scavenging cytotoxic aldehydes;however, few AKRs have been reported to enhance Cd stress tolerance. In this study, the gene Ib AKR was isolated from sweet potato. The relative expression levels of Ib AKR increased significantly(approximately 3-fold) after exposure to 200 mmol$L–1 Cd Cl2 or 10 mmol$L–1 H2 O2. A subcellular localization assay showed that Ib AKR is predominantly located in the nucleus and cytoplasm.Ib AKR-overexpressing tobacco plants showed higher tolerance to Cd stress than wild-type(WT). Transgenic lines showed a significant ability to scavenge malondialdehyde(MDA) and methylglyoxal(MG). In addition,proline content and superoxide dismutase activity were significantly higher and H2 O2 levels were significantly lower in the transgenic plants than in the WT. Quantitative real-time PCR analysis showed that the reactive oxygen species(ROS) scavenging genes encoding guaiacol peroxidase(GPX), ascorbate peroxidase(APX), monodehydroascorbate reductase(MDHAR) and peroxidase(POD) were significantly upregulated in transgenic plants compared to WT under Cd stress. These findings suggest that overexpressing Ib AKR enhances tolerance to Cd stress via the scavenging of cytotoxic aldehydes and the activation of the ROS scavenging system.展开更多
Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme s...Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme seedlings in response to inorganic Cd stress,we cultured the seedlings under two different Cd levels:natural seawater and high Cd stress.High Cd stress significantly inhibited the seedlings growth,and darkened the thalli color.Additionally,the pigment contents,growth rate,peroxidase(POD)activity,dehydroascorbic acid(DHA)content,and glutathione reductase(GR)activity in S.fusiforme were significantly reduced by high Cd treatment.Contrarily,the Cd accumulation,Cd2+absorption rate,dark respiration/net photosynthetic rate(Rd/Pn),ascorbic acid(Vc)content,soluble protein(SP)content,glutathione(GSH),and the activities of superoxide dismutase(SOD)and catalase(CAT)of S.fusiforme under Cd treatment significantly increased compared to the control group.The decrease of malondialdehyde(MDA)was not significant.Although S.fusiforme seedlings increased the antioxidant activities of POD,SOD,Vc,and the AsA-GSH cycle to disseminate H2O2 and maintain healthy metabolism,high Cd stress caused Cd accumulation in the stem and leaves of S.fusiforme seedlings.The excessive Cd significantly restricted photosynthesis and reduced photosynthetic pigments in the seedlings,resulting in growth inhibition and deep morphological color,especially of the stems.High levels of Cd in seawater had toxic effects on commercial S.fusiforme seedlings,and risked this edible seaweed for human food.展开更多
Potentilla sericea is a heavy metal hyperaccumulator landscaping plant.MYB transcription factors play an important role in regulating plant stress response to adversity.However,there are few studies on MYB transcripti...Potentilla sericea is a heavy metal hyperaccumulator landscaping plant.MYB transcription factors play an important role in regulating plant stress response to adversity.However,there are few studies on MYB transcription factors in stress tolerance in Potentilla sericea.In this study,the PsMYB62 gene was successfully cloned from Potentilla sericea.Methods:Bioinformatic analysis and real-time quantitative PCR(qPCR)methods were used to evaluate this gene.The transgenic A.thaliana were obtained by flower dipping and the gene function was identified by determining physiological indicators under cadmium stress.Results:The open reading frame of PsMYB62 is 942 bp,which encodes 313 amino acids(aa)and belongs to the R2R3 MYB transcription factor.The plant overexpression vector PBI121-PsMYB62-GFP was constructed and successfully transferred into A.thaliana.The relative expression level of PsMYB62 was significantly increased by CdCl_(2),NaCl,ABA,and mannitol treatments.The germination rate of transgenic seeds was higher than those of wild type(WT)and empty vector(EV)under different concentrations of cadmium treatment.Upon treatment with 100μmol·L^(−1)of CdCl_(2)·2.5H_(2)O,the activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)in the transgenic plants were significantly higher than those in the WT and EV.The contents of H_(2)O_(2),O_(2)·−and malondialdehyde(MDA)in transgenic lines were increased,but lower than those in WT and EV.The expression levels of AtGSH,AtPCS,and AtNAS4 that were related to the regulation of cadmium were increased,but the expression levels of transgenic lines were higher than those of WT and EV.Conclusion:The above results showed that PsMYB62 could be induced by cadmium and could improve the cadmium resistance of plants.展开更多
The gene AtCSR encodes peptidyl-prolyl cis/trans isomerases (PPIases) that accelerate energetically unfavorable cis/trans isomerization of the peptide bond preceding proline production.In our studies,we found that AtC...The gene AtCSR encodes peptidyl-prolyl cis/trans isomerases (PPIases) that accelerate energetically unfavorable cis/trans isomerization of the peptide bond preceding proline production.In our studies,we found that AtCSR was associated with cadmium (Cd)-sensitive response in Arabidopsis.Our results show that AtCSR expression was triggered by Cd-stress in wild type Arabidopsis.The expression of some genes responsible for Cd2+ transportation into vacuoles was induced,and the expression of the iron-regulated transporter 1 (IRT1) related to Cd2+ absorption from the environment was not induced in wild type with Cd2+ treatment.The expression of Cd-transportation related genes was not in response to Cd-stress,whereas IRT expression increased dramatically in atcsr-2 with Cd2+ treatment.The expression of glutathione 1 (GSH1) was consistent with GSH being much lower in atcsr-2 in comparison with the wild type with Cd2+ treatment.Additionally,malondialdehyde (MDA),hydrogen peroxide,and Cd2+ contents,and activities of some antioxidative enzymes,differed between the wild type and atcsr-2.Hydrogen sulfide (H2S) has been confirmed as the third gas-transmitter over recent years.The findings revealed that the expression pattern of H2 S-releasing related genes and that of Cd-induced chelation and transportation genes matched well in the wild type and atcsr-2,and H2S could regulate the expression of the Cd-induced genes and alleviate Cd-triggered toxicity.Finally,one possible suggestion was given:down-regulation of atcsr-2,depending on H2S gas-transmitter not only weakened Cd2+ chelation,but also reduced Cd2+ transportation into vacuoles,as well as enhancing the Cd2+ assimilation,thus rendering atcsr-2 mutant sensitive to Cd-stress.展开更多
The stress effect of cadmium absorption between aloe and Solanum nigrum L was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomas...The stress effect of cadmium absorption between aloe and Solanum nigrum L was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass and Cd content in the plants of aloe and S. nigrum L were closely related to Cd content in the soil, and S. nigrum L and aloe had a strong tolerance to Cd in the experiment, pH of rhizosphere soil with S. ni- grum L and aloe planted was generally higher than that of non-rhizosphere soil, which is related to the planting pattern. Compared with aloe, S. nig- rum L had a stronger capacity to accumulate Cd, and intercropping S. nigrum L and aloe could inhibit aloe's absorption of Cd, which is favorable to the safe planting of aloe. In addition, S. nigrum L has the potential to restore polluted soil.展开更多
Objective To investigate the cytotoxic mechanism of cadmium(Cd) on cerebral cortical neurons.Methods The primary cultures of rat cerebral cortical neurons were treated with different concentrations of cadmium acetat...Objective To investigate the cytotoxic mechanism of cadmium(Cd) on cerebral cortical neurons.Methods The primary cultures of rat cerebral cortical neurons were treated with different concentrations of cadmium acetate(0,5,10,and 20 μmol/L),and then the cell viability,apoptosis,ultrastructure,intracellular [Ca2+]i and reactive oxygen species(ROS) levels,mitochondrial membrane potential(ΔΨ),activities of catalase(CAT) and superoxide dismutase(SOD) were measured.Results A progressive loss in cell viability and an increased number of apoptotic cells were observed.In addition,Cd-induced apoptotic morphological changes in cerebral cortical neurons were also demonstrated by Hoechst 33258 staining.Meanwhile,ultrastructural changes were distortion of mitochondrial cristae and an unusual arrangement.Simultaneously,elevation of intracellular [Ca2+]i and ROS levels,depletion of ΔΨ were revealed in a dose-dependent manner during the exposure.Moreover,CAT and SOD activities in the living cells increased significantly.Conclusion Exposure of cortical neurons to different doses of Cd led to cellular death,mediated by an apoptotic mechanism,and the apoptotic death induced by oxidative stress may be a potential reason.And the disorder of intracellular homeostasis caused by oxidative stress and mitochondrial dysfunction may be a trigger for apoptosis in cortical neurons.展开更多
Objective This study was conducted to investigate the regulation of endoplasmic reticulum stress on Nrf2 signaling pathway in the kidneys of rats. Methods Rats were divided into twelve groups of six animals each. Some...Objective This study was conducted to investigate the regulation of endoplasmic reticulum stress on Nrf2 signaling pathway in the kidneys of rats. Methods Rats were divided into twelve groups of six animals each. Some groups were pre-administered with bacitracin or tauroursodeoxycholic acid(TUDCA), and all of them were treated with 5-20 μmol/kg cadmium(Cd) for 48 h. The oxidative stress levels were analyzed using kits. The mRNA and protein expression levels of endoplasmic reticulum stress-related factors and Nrf2 signaling pathway-related factors were determined using RT-PCR and western blot. Results Cd exposure resulted in oxidative stress in the kidneys of rats and upregulated the expression of endoplasmic reticulum stress(ERS)-related factors and Nrf2 signaling pathway-related factors, especially at doses of 10 and 20 μmol/kg Cd, and the expression changes were particularly obvious. Moreover, after pretreatment with bacitracin, Cd upregulated the expression of ERS-related factors to a certain extent and, at higher doses, increased the mRNA expression of Nrf2. After pretreatment with TUDCA, Cd reduced the level of ERS to a certain extent; however, at these doses, there were no significant changes in the expression of Nrf2. Conclusion Cadmium can result in ERS and oxidative stress in the kidneys of rats, activate Nrf2, and upregulate the transcriptional expression of phase II detoxification enzymes under these experimental conditions. ERS has a positive regulation effect on Nrf2 signaling pathway but has little effect on the negative regulation of Nrf2 signaling pathway in cadmium toxicity.展开更多
The stress effect of cadmium absorption between aloe and Brassica junica was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass...The stress effect of cadmium absorption between aloe and Brassica junica was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass and cadmium content of aloe and B. junica plants were relat- ed to pH and cadmium content in the soil. When aloe was intercropped with B. junica, soil pH was higher than that of single planting, showing that intercropping aloe and B. junica can reduce aloe's absorption of Cd. When Cd content in the soil was high, the absorption coefficient of aloe was lower than that of B. junica, and C,d content in the leaves of intercropped aloe was 15.8% -79.2% lower than that of aloe cropped only. In addi- tion, planting B. junica in the soil with different contents of Cd had certain stress effect on aloe's absorption of Cd, thereby protecting aloe well, im- proving safety of aloe planting and showing its potential for application in phytoremediation.展开更多
基金funded by the Project of Fiber Crops Industrial System Construction in China (CARS-19-E06)the Project for Constructing Observations Station of Scientific Experiment of Jute and Kenaf in the South East of China, Ministry of Agriculture of China (2011.9)the Construction of Germplasm Resources Plat form for BastFiber Crops in Fujian, China (2010N2002)
文摘The effects of cadmium stress on the growth, antioxidative enzymes and lipid peroxidation in two kenaf plants, Fuhong 991 and ZM412, were analysed under control (0.5-strength Hoagland's nutrient solution) or five levels of cadmium stress (0.5- strength Hoagland's nutrient solution containing different concentrations of Cd2+). The leaves and roots of control and cadmium-stressed plants were harvested after 3 wk. At the same Cd concentration, the Cd tolerance index of Fuhong 991 was higher than that of ZM412, indicating that Fuhong 991 may be more tolerant to Cd than ZM412. The superoxide dismutase (SOD), catalase activity (CAT) and peroxidase (POD) activities fluctuated in the leaves of the Cd-stressed plants compared to the control, whereas the glutathione reductase activity (GR) was much larger than the control for Fuhong 991, ensuring that sufficient quantities of GSH were available to respond to the cadmium stress. In comparison to the control, the dynamic tendency of the SOD, CAT and POD activities in roots of the Cd-stressed plants all increased and then declined, but the POD activity of Fuhong 991 remained nearly unchanged at all of the stress levels. The increase in the enzyme activities demonstrated that Fuhong 991 was more tolerant to cadmium than ZM 412. The lipid peroxidation was enhanced only in the leaves of Cd-stressed ZM 412. These findings indicated that antioxidative activities may play important roles in Cd-stressed Fuhong 991 and ZM 412 and that the leaf and root cell membranes of Fuhong 991 have a greater stability than those of ZM 412. For pollution monitoring purposes, the GR activity in the roots and leaves may serve as a biomarker of Cd for Fuhong 991, whereas lipid peroxidation may serve as biomarker for ZM 412.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.30700479)China Postdoctoral Science Foundation(Grant No.20060390288).
文摘A hydroponic culture experiment was done to investigate the effect of Cd stress on glutathione content (GSH) and glutathione S-transferase (GST, EC 2.5.1,18) activity in rice seedlings. The rice growth was severely inhibited when Cd level in the solution was higher than 10 mg/L. In rice shoots, GSH content and GST activity increased with the increasing Cd level, while in roots, GST was obviously inhibited by Cd treatments, Compared with shoots, the rice roots had higher GSH content and GST activity, indicating the ability of Cd detoxification was much higher in roots than in shoots. There was a significant correlation between Cd level and GSH content or GST activity, suggesting that both parameters may be used as biomarkers of Cd stress in rice.
基金supported by the Key Scientific and Technological Programme of Jiangxi Province,China(20121BBF60036)the Special Fund for Agro-scientific Research in the Public Interest,State Agriculture Ministry of China(200903028)+2 种基金the Science and Technology Landing Project of Jiangxi Province,China(KJLD12001)the Youth Fund of the Education Department of Jiangxi Province,China(GJJ14219)the National Natural Science Foundation of China(31160534)
文摘The B cells translocation gene 1 (BTG1) is a member of the BTG/TOB family of anti-proliferative genes, which have recently emerged as important regulators of cell growth and differentiation among vertebrates. Here, for the first time we cloned the full-length eDNA sequence of Hyriopsis schlegelii (Hs-BTG1), an economically important freshwater shellfish and potential indicator of environmental heavy metal pollution, for the first time. Using rapid amplification of eDNA ends (RACE) together with splicing the EST sequence from a haemocyte eDNA library, we found that Hs-BTG1 contains a 525 bp open reading frame (ORF) encoding a 174 amino-acid polypeptide, a 306 bp 5' untranslated region (5' UTR), and a 571 bp 3' UTR with a Poly(A) tail as well as a transcription termination signal (AATAAA). Homologne searching against GenBank revealed that Hs-BTG1 was closest to Crassostrea gigas BTG1, sharing 50.57% of protein identities. Hs-BTG1 also shares some typical features of the BTG/TOB family, possessing two well-conserved A and B boxes. Clustering analysis of Hs-BTG1 and other known BTGs showed that Hs-BTG1 was also closely related to BTG1 of C. gigas from the invertebrate BTG1 clade. Function prediction via homology modeling showed that both Hs-BTG1 and C. gigas BTG1 share a similar three-dimensional structure with Homo sapiens BTG1. Tissue-specific expression analysis of the Hs-BTG1 via real-time PCR showed that the transcripts were constitutively expressed, with the highest levels in the hepatopancreas and gills, and the lowest in both haemocyte and muscle tissue. Expression levels of Hs-BTG1 in hepatopancreas (2.03-fold), mantle (2.07-fold), kidney (2.2-fold) and haemocyte (2.5-fold) were enhanced by cadmium (Cd2+) stress, suggesting that Hs-BTG 1 may have played a significant role in H, schlegelii adaptation to adverse environmental conditions.
基金supported by the National Natural Science Foundation of China (41201317)the Key Technologies R&D Program of China during the 12th Five-Year Plan period (2012BAD14B01)
文摘It is of great importance to solve the threats induced by cadmium pollution on crops. This paper examined the effect of biochar on cadmium accumulation in japonica rice and revealed the mechanism underlying the response of protective enzyme system to cadmium stress. Biochar derived from rice straw was applied at two application rates under three cadmium concentrations. Shennong 265, super japonica rice variety, was selected as the test crop. The results indicated that cadmium content in above-ground biomass of rice increased with increasing soil cadmium concentrations, but the biochar application could suppress the accumulation of cadmium to some extent. Under high concentrations of cadmium, content of free proline and MDA (malondialdehyde) were high, so did the SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) activity in the flag leaf of rice. However, the protective enzyme activities remained at low level when biochar was added.
基金supported by Hangzhou Scientific and Technological Program(20170432B03)the National Key Technology Research and Development Program(2015BAD01B02)the National Natural Science Foundation of China(31661143006).
文摘Melatonin(MLT)is a hormonal substance found in many organisms and can improve plant stress resistance.In this study,the japonica rice variety Y32 and indica rice variety NJ6 were cultivated in hydroponics under different concentrations of CdCl2 at the two-leaf stage.The growth,physiological and biochemical responses of the seedlings and the expression of cadmium(Cd)-related genes under exogenous melatonin(MLT)treatment were assessed.The results indicated that Cd stress destroyed the dynamic balance between reactive oxygen species(ROS)production and removal,resulting in ROS accumulation,membrane lipid peroxidation,and impaired growth and development.Following the application of exogenous MLT to rice seedlings,increases in plant biomass including both underground and above-ground areas were observed.MLT also scavenged the inhibition of superoxide dismutase(SOD)and peroxidase(POD)in a concentration dependent manner in response to Cd stress.Catalase(CAT)activity and malondialdehyde(MDA)expression also decreased following MLT treatment.Amongst the six Cd-related genes assessed,five genes were downregulated and one was up-regulated in response to MLT treatment.Taken together,these data demonstrate that MLT improves the resilience of rice seedlings at the biochemical,physiological,and molecular levels,and diminishes the damage caused by Cd stress.
基金Financial supports from the National Natural Science Foundation of China(Grant No.30700479)Research Fund for the Doctoral Program of Higher Education of China(Grant Nos.20090097110035 and 20110097110004)Research Fund of State Key Laboratory of Soil and Sustainable Agriculture,Nanjing Institute of Soil Science,Chinese Academy of Science,China(Grant No.Y052010019) are greatly acknowledged
文摘Cadmium (Cd) contamination in paddy soils poses a serious threat to the production and quality of rice. Among various biochemical processes related to Cd detoxification in rice, glutathione S-transferase (GST) plays an important role, catalyzing Cd complexation with glutathione (GSH) and scavenging reactive oxygen species (ROS) in cells. In this study, a hydroponic experiment was conducted to investigate the response of GST isozymes in rice roots upon Cd exposure. Results showed that the GST activity in rice roots was clearly enhanced by 50 pmol/L Cd treatment for 7 d. The GST isozymes were purified by ammonium sulphate precipitation, gel filtration chromatography and affinity chromatography. After being separated by SDS-PAGE and visualized by silver staining, GSTU6 was identified by in-gel digestion, MALDI-TOF-MS analysis and peptide mass fingerprint. The results confirm the vital function of tau class rice GST in Cd detoxification.
基金supported by the National Natural Science Foundation of China (Grant No. 30300026)
文摘A proteomic approach including two-dimensional electrophoresis and mass spectrometric (MALDI-TOF MS) analyses was used to investigate the responses to cadmium (Cd) stress in seedlings of rice (Oryza sativa L.) varieties Shanyou 63 and Aizaizhan. Cd stress significantly inhibited root and shoot growth, and affected the global proteome in rice roots and leaves, which induced or upregulated the expression of corresponding proteins in rice roots and leaves when rice seedlings were exposed to 0.1 or 1.0 mmol/L Cd. The Cd-induced proteins are involved in chelation and compartmentation of Cd, elimination of active oxygen free radicals, detoxification of toxic substances, degradation of denatured proteins or inactivated enzymes, regulation of physiologic metabolism and induction of pathogenesis-related proteins. Comparing the Cd-induced proteins between the two vadeties, the β-glucosidase and pathogenesis-related protein family 10 proteins were more drastically induced by Cd stress in roots and leaves of Aizaizhan, and the UDP-glucose protein transglucosylase and translational elongation factor Tu were induced by 0.1 mmol/L Cd stress in roots of Shanyou 63. This may be one of the important mechanisms for higher tolerance to Cd stress in Shanyou 63 than in Aizaizhan.
基金supported by the Foundation for Young Scientist of Beijing Academy of Agriculture & Forestry Sciences, China (QNJJ201505)the National Key Research and Development Program of China (SQ2016ZY03002163)
文摘Toxic symptoms and tolerance mechanisms of heavy metal in maize are well documented. However, limited information is available regarding the changes in the proteome of maize seedling roots in response to cadmium(Cd) stress. Here, we employed an i TRAQ-based quantitative proteomic approach to characterize the dynamic alterations in the root proteome during early developmental in maize seedling. We conducted our proteomic experiments in three-day seedling subjected to Cd stress, using roots in four time points. We identified a total of 733, 307, 499, and 576 differentially abundant proteins after 12, 24, 48, or 72 h of treatment, respectively. These proteins displayed different functions, such as ribosomal synthesis, reactive oxygen species homeostasis, cell wall organization, cellular metabolism, and carbohydrate and energy metabolism. Of the 166 and 177 proteins with higher and lower abundance identified in at least two time points, 14 were common for three time points. We selected nine proteins to verify their expression using quantitative real-time PCR. Proteins involved in the ribosome pathway were especially responsive to Cd stress. Functional characterization of the proteins and the pathways identified in this study could help our understanding of the complicated molecular mechanism involved in Cd stress responses and create a list of candidate gene responsible for Cd tolerance in maize seeding roots.
基金supported by the National Natural Science Foundation of China(No.30671126)Shandong Province(No.Y2006D22)
文摘The link between root growth, H2O2, auxin signaling, and the ceil cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) was analyzed in this study. Exposure to Cd induced a significant accumulation of Cd, but caused a decrease in zinc (Zn) content which resulted from the decreased expression of OsHMA9 and OsZIP. Analysis using a Cd-specific probe showed that Cd was mainly localized in the meristematic zone and vascular tissues. Formation and elongation of the root system were significantly promoted by 3-amino-l,2,4-triazole (AT), but were markedly inhibited by N,N'. dimethylthiourea (DMTU) under Cd stress. The effect of H2O2 on Cd-stressed root growth was further confirmed by examining a gain-of-function rice mutant (carrying catalasel and glutathione-S-transferase) in the presence or absence of diphenylene iodonium. DR5-GUS staining revealed close associations between H2O2 and the concentration and distribution of auxin. H2O2 affected the expression of key genes, including OsYUCCA, OsPIN, OsARF, and OslAA, in the auxin signaling pathway in Cd-treated plants. These results suggest that H2O2 functions upstream of the auxin signaling pathway. Furthermore, H2O2 modified the expression of cell-cycle genes in Cd-treated roots. The effects of H2O2 on root system growth are therefore linked to auxin signal modification and to variations in the expression of cell-cycle genes in Cd-stressed rice. A working model for the effects of H2O2 on Cd-stressed root system growth is thus proposed and discussed in this paper.
基金supported by the Candidates of the Young and Middle Aged Academic Leaders of Yunnan Province (2015HB095)the Youth Innovation Promotion Association of CAS
文摘Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-responsive genes were induced by Cd treat- ment, and that their upregulation was suppressed in bhlh104 loss-of-function mutants, but enhanced upon overexpression of bHLH104. Correspondingly, the bhlh104 mutants displayed sensitivity to Cd stress, whereas plants overexpressing bHLH104 exhibited enhanced Cd tolerance. Further analysis suggested that bHLH104 positivelyregulates four heavy metal detoxification-associated genes, IREG2, A4TP3, HA4A3 and NAS4, which play roles in Cd sequestration and tolerance. The bHLH104 overexpres- sion plants accumulated high levels of Cd in the root but low levels of Cd in the shoot, which might contribute to the Cd tolerance in those lines. The present study thus points to bHLH104 as a potentially useful tool for genetic engineering of plants with enhanced Cd tolerance.
基金supported by the National Natural Science Foundation of China (31271777)the China Agriculture Research System (CARS-10, Sweet potato)
文摘High concentrations of Cd can inhibit growth and reduce the activity of the photosynthetic apparatus in plants. In several plant species, aldo-keto reductases(AKRs) have been shown to enhance tolerance to various abiotic stresses by scavenging cytotoxic aldehydes;however, few AKRs have been reported to enhance Cd stress tolerance. In this study, the gene Ib AKR was isolated from sweet potato. The relative expression levels of Ib AKR increased significantly(approximately 3-fold) after exposure to 200 mmol$L–1 Cd Cl2 or 10 mmol$L–1 H2 O2. A subcellular localization assay showed that Ib AKR is predominantly located in the nucleus and cytoplasm.Ib AKR-overexpressing tobacco plants showed higher tolerance to Cd stress than wild-type(WT). Transgenic lines showed a significant ability to scavenge malondialdehyde(MDA) and methylglyoxal(MG). In addition,proline content and superoxide dismutase activity were significantly higher and H2 O2 levels were significantly lower in the transgenic plants than in the WT. Quantitative real-time PCR analysis showed that the reactive oxygen species(ROS) scavenging genes encoding guaiacol peroxidase(GPX), ascorbate peroxidase(APX), monodehydroascorbate reductase(MDHAR) and peroxidase(POD) were significantly upregulated in transgenic plants compared to WT under Cd stress. These findings suggest that overexpressing Ib AKR enhances tolerance to Cd stress via the scavenging of cytotoxic aldehydes and the activation of the ROS scavenging system.
基金Foundation item:The National Key R&D Program of China under contract No.2018YFD0901500the National Natural Science Foundation of China under contract Nos 41706147 and 41876124.
文摘Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme seedlings in response to inorganic Cd stress,we cultured the seedlings under two different Cd levels:natural seawater and high Cd stress.High Cd stress significantly inhibited the seedlings growth,and darkened the thalli color.Additionally,the pigment contents,growth rate,peroxidase(POD)activity,dehydroascorbic acid(DHA)content,and glutathione reductase(GR)activity in S.fusiforme were significantly reduced by high Cd treatment.Contrarily,the Cd accumulation,Cd2+absorption rate,dark respiration/net photosynthetic rate(Rd/Pn),ascorbic acid(Vc)content,soluble protein(SP)content,glutathione(GSH),and the activities of superoxide dismutase(SOD)and catalase(CAT)of S.fusiforme under Cd treatment significantly increased compared to the control group.The decrease of malondialdehyde(MDA)was not significant.Although S.fusiforme seedlings increased the antioxidant activities of POD,SOD,Vc,and the AsA-GSH cycle to disseminate H2O2 and maintain healthy metabolism,high Cd stress caused Cd accumulation in the stem and leaves of S.fusiforme seedlings.The excessive Cd significantly restricted photosynthesis and reduced photosynthetic pigments in the seedlings,resulting in growth inhibition and deep morphological color,especially of the stems.High levels of Cd in seawater had toxic effects on commercial S.fusiforme seedlings,and risked this edible seaweed for human food.
基金funded by the Natural Science Foundation of Heilongjiang Province(LH2020C045).
文摘Potentilla sericea is a heavy metal hyperaccumulator landscaping plant.MYB transcription factors play an important role in regulating plant stress response to adversity.However,there are few studies on MYB transcription factors in stress tolerance in Potentilla sericea.In this study,the PsMYB62 gene was successfully cloned from Potentilla sericea.Methods:Bioinformatic analysis and real-time quantitative PCR(qPCR)methods were used to evaluate this gene.The transgenic A.thaliana were obtained by flower dipping and the gene function was identified by determining physiological indicators under cadmium stress.Results:The open reading frame of PsMYB62 is 942 bp,which encodes 313 amino acids(aa)and belongs to the R2R3 MYB transcription factor.The plant overexpression vector PBI121-PsMYB62-GFP was constructed and successfully transferred into A.thaliana.The relative expression level of PsMYB62 was significantly increased by CdCl_(2),NaCl,ABA,and mannitol treatments.The germination rate of transgenic seeds was higher than those of wild type(WT)and empty vector(EV)under different concentrations of cadmium treatment.Upon treatment with 100μmol·L^(−1)of CdCl_(2)·2.5H_(2)O,the activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)in the transgenic plants were significantly higher than those in the WT and EV.The contents of H_(2)O_(2),O_(2)·−and malondialdehyde(MDA)in transgenic lines were increased,but lower than those in WT and EV.The expression levels of AtGSH,AtPCS,and AtNAS4 that were related to the regulation of cadmium were increased,but the expression levels of transgenic lines were higher than those of WT and EV.Conclusion:The above results showed that PsMYB62 could be induced by cadmium and could improve the cadmium resistance of plants.
基金Project supported by the Research Fund for the Doctoral Program of Higher Education of China (No. 20091401110004)the Science and Technology Special Project of Shanxi Province,China (2012,to QiangZHANG)the Shanxi Scholarship Council of China (No. 2011-007)
文摘The gene AtCSR encodes peptidyl-prolyl cis/trans isomerases (PPIases) that accelerate energetically unfavorable cis/trans isomerization of the peptide bond preceding proline production.In our studies,we found that AtCSR was associated with cadmium (Cd)-sensitive response in Arabidopsis.Our results show that AtCSR expression was triggered by Cd-stress in wild type Arabidopsis.The expression of some genes responsible for Cd2+ transportation into vacuoles was induced,and the expression of the iron-regulated transporter 1 (IRT1) related to Cd2+ absorption from the environment was not induced in wild type with Cd2+ treatment.The expression of Cd-transportation related genes was not in response to Cd-stress,whereas IRT expression increased dramatically in atcsr-2 with Cd2+ treatment.The expression of glutathione 1 (GSH1) was consistent with GSH being much lower in atcsr-2 in comparison with the wild type with Cd2+ treatment.Additionally,malondialdehyde (MDA),hydrogen peroxide,and Cd2+ contents,and activities of some antioxidative enzymes,differed between the wild type and atcsr-2.Hydrogen sulfide (H2S) has been confirmed as the third gas-transmitter over recent years.The findings revealed that the expression pattern of H2 S-releasing related genes and that of Cd-induced chelation and transportation genes matched well in the wild type and atcsr-2,and H2S could regulate the expression of the Cd-induced genes and alleviate Cd-triggered toxicity.Finally,one possible suggestion was given:down-regulation of atcsr-2,depending on H2S gas-transmitter not only weakened Cd2+ chelation,but also reduced Cd2+ transportation into vacuoles,as well as enhancing the Cd2+ assimilation,thus rendering atcsr-2 mutant sensitive to Cd-stress.
基金Supported by the Scientific Research Project of Public Welfare Industry of Ministry of Land and Resources,China(201111020-7)National Innovation Experimental Project for Undergraduates(201311078017)+1 种基金Scientific Research Project of Guangzhou Higher Education(10A062)Plan Project for Emerging Talents of Guangzhou University(2011)
文摘The stress effect of cadmium absorption between aloe and Solanum nigrum L was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass and Cd content in the plants of aloe and S. nigrum L were closely related to Cd content in the soil, and S. nigrum L and aloe had a strong tolerance to Cd in the experiment, pH of rhizosphere soil with S. ni- grum L and aloe planted was generally higher than that of non-rhizosphere soil, which is related to the planting pattern. Compared with aloe, S. nig- rum L had a stronger capacity to accumulate Cd, and intercropping S. nigrum L and aloe could inhibit aloe's absorption of Cd, which is favorable to the safe planting of aloe. In addition, S. nigrum L has the potential to restore polluted soil.
基金supported by the National Nature Science Foundation of China (no.30972229 and 31101866)a project Funded by Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Objective To investigate the cytotoxic mechanism of cadmium(Cd) on cerebral cortical neurons.Methods The primary cultures of rat cerebral cortical neurons were treated with different concentrations of cadmium acetate(0,5,10,and 20 μmol/L),and then the cell viability,apoptosis,ultrastructure,intracellular [Ca2+]i and reactive oxygen species(ROS) levels,mitochondrial membrane potential(ΔΨ),activities of catalase(CAT) and superoxide dismutase(SOD) were measured.Results A progressive loss in cell viability and an increased number of apoptotic cells were observed.In addition,Cd-induced apoptotic morphological changes in cerebral cortical neurons were also demonstrated by Hoechst 33258 staining.Meanwhile,ultrastructural changes were distortion of mitochondrial cristae and an unusual arrangement.Simultaneously,elevation of intracellular [Ca2+]i and ROS levels,depletion of ΔΨ were revealed in a dose-dependent manner during the exposure.Moreover,CAT and SOD activities in the living cells increased significantly.Conclusion Exposure of cortical neurons to different doses of Cd led to cellular death,mediated by an apoptotic mechanism,and the apoptotic death induced by oxidative stress may be a potential reason.And the disorder of intracellular homeostasis caused by oxidative stress and mitochondrial dysfunction may be a trigger for apoptosis in cortical neurons.
基金supported by grants from the Science and Technology Plan Project of Shenzhen City in China [No.JCYJ20140414154847275]
文摘Objective This study was conducted to investigate the regulation of endoplasmic reticulum stress on Nrf2 signaling pathway in the kidneys of rats. Methods Rats were divided into twelve groups of six animals each. Some groups were pre-administered with bacitracin or tauroursodeoxycholic acid(TUDCA), and all of them were treated with 5-20 μmol/kg cadmium(Cd) for 48 h. The oxidative stress levels were analyzed using kits. The mRNA and protein expression levels of endoplasmic reticulum stress-related factors and Nrf2 signaling pathway-related factors were determined using RT-PCR and western blot. Results Cd exposure resulted in oxidative stress in the kidneys of rats and upregulated the expression of endoplasmic reticulum stress(ERS)-related factors and Nrf2 signaling pathway-related factors, especially at doses of 10 and 20 μmol/kg Cd, and the expression changes were particularly obvious. Moreover, after pretreatment with bacitracin, Cd upregulated the expression of ERS-related factors to a certain extent and, at higher doses, increased the mRNA expression of Nrf2. After pretreatment with TUDCA, Cd reduced the level of ERS to a certain extent; however, at these doses, there were no significant changes in the expression of Nrf2. Conclusion Cadmium can result in ERS and oxidative stress in the kidneys of rats, activate Nrf2, and upregulate the transcriptional expression of phase II detoxification enzymes under these experimental conditions. ERS has a positive regulation effect on Nrf2 signaling pathway but has little effect on the negative regulation of Nrf2 signaling pathway in cadmium toxicity.
基金Supported by the Scientific Research Project of Public Welfare Industry of Ministry of Land and Resources,China(201111020-7)National Innovation Experimental Project for Undergraduates(201311078017)Scientific Research Project of Guangzhou Higher Education(10A062)
文摘The stress effect of cadmium absorption between aloe and Brassica junica was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass and cadmium content of aloe and B. junica plants were relat- ed to pH and cadmium content in the soil. When aloe was intercropped with B. junica, soil pH was higher than that of single planting, showing that intercropping aloe and B. junica can reduce aloe's absorption of Cd. When Cd content in the soil was high, the absorption coefficient of aloe was lower than that of B. junica, and C,d content in the leaves of intercropped aloe was 15.8% -79.2% lower than that of aloe cropped only. In addi- tion, planting B. junica in the soil with different contents of Cd had certain stress effect on aloe's absorption of Cd, thereby protecting aloe well, im- proving safety of aloe planting and showing its potential for application in phytoremediation.