Comparative physiological and transcriptomic analyses reveal ascorbate and glutathione coregulation of cadmium toxicity resistance in wheat genotypes

Abstract Background Cadmium (Cd) is a heavy metal with high toxicity that severely inhibits wheat growth and development. Cd easily accumulates in wheat kernels and enters the human food chain. Genetic variation in the resistance to Cd toxicity found in wheat genotypes emphasizes the complex response architecture. Understanding the Cd resistance mechanisms is crucial for combating Cd phytotoxicity and meeting the increasing daily food demand. Results Using two wheat genotypes (Cd resistant and sensitive genotypes T207 and S276, respectively) with differing root growth responses to Cd, we conducted comparative physiological and transcriptomic analyses and exogenous application tests to evaluate Cd detoxification mechanisms. S276 accumulated more H2O2, O2−, and MDA than T207 under Cd toxicity. Catalase activity and levels of ascorbic acid (AsA) and glutathione (GSH) were greater, whereas superoxide dismutase (SOD) and peroxidase (POD) activities were lower in T207 than in S276. Transcriptomic analysis showed that the expression of RBOHA, RBOHC, and RBOHE was significantly increased under Cd toxicity, and two-thirds (22 genes) of the differentially expressed RBOH genes had higher expression levels in S276 than inT207. Cd toxicity reshaped the transcriptional profiling of the genes involving the AsA-GSH cycle, and a larger proportion (74.25%) of the corresponding differentially expressed genes showed higher expression in T207 than S276. The combined exogenous application of AsA and GSH alleviated Cd toxicity by scavenging excess ROS and coordinately promoting root length and branching, especially in S276. Conclusions The results indicated that the ROS homeostasis plays a key role in differential Cd resistance in wheat genotypes, and the AsA-GSH cycle fundamentally and vigorously influences wheat defense against Cd toxicity, providing insight into the physiological and transcriptional mechanisms underlying Cd detoxification.

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Identification and profiling of microRNAs responsive to cadmium toxicity in hepatopancreas of the freshwater crab Sinopotamon henanense

Hereditas ◽

10.1186/s41065-019-0110-z ◽

2019 ◽

Vol 156 (1) ◽

Author(s):

Peng Xu ◽

Huiqin Guo ◽

Huihui Wang ◽

Yuxin Xie ◽

Shao Chin Lee ◽

...

Keyword(s):

Transcriptional Regulatory Network ◽

Cadmium Toxicity ◽

Functional Adaptation ◽

Differentially Expressed ◽

Portunus Trituberculatus ◽

Freshwater Crab ◽

Cd Toxicity ◽

Qrt Pcr ◽

Differentially Expressed Mirnas ◽

Sinopotamon Henanense

Abstract Background Cadmium (Cd) is a ubiquitous environmental toxicant for aquatic animals. The freshwater crab, Sinopotamon henanense (S. henanense), is a useful model for monitoring Cd exposure since it is widely distributed in sediments whereby it tends to accumulate several toxicants, including Cd. In the recent years, the toxic effects of Cd in the hepatopancreas of S. henanense have been demonstrated by a series of biochemical analysis and ultrastructural observations as well as the deep sequencing approaches and gene expression profile analysis. However, the post-transcriptional regulatory network underlying Cd toxicity in S.henanense is still largely unknown. Results The miRNA transcriptional profile of the hepatopancreas of S. henanense was used to investigate the expression levels of miRNAs in response to Cd toxicity. In total, 464 known miRNAs and 191 novel miRNAs were identified. Among these 656 miRNAs, 126 known miRNAs could be matched with the miRNAs of Portunus trituberculatus, Eriocheir sinensis and Scylla paramamosain. Furthermore, a total of 24 conserved miRNAs were detected in these four crab species. Fifty-one differentially expressed miRNAs were identified in the Cd-exposed group, with 31 up-regulated and 20 down-regulated. Eight of the differentially expressed miRNAs were randomly selected and verified by the quantitative real-time PCR (qRT-PCR), and there was a general consistency (87.25%) between the qRT-PCR and miRNA transcriptome data. A total of 5258 target genes were screened by bioinformatics prediction. GO term analysis showed that, 17 GO terms were significantly enriched, which were mainly related to the regulation of oxidoreductase activity. KEGG pathway analysis showed that 18 pathways were significantly enriched, which were mainly associated with the biosynthesis, modification and degradation of proteins. Conclusion In response to Cd toxicity, in the hepatopancreas of S. henanense, the expressions of significant amount of miRNAs were altered, which may be an adaptation to resist the oxidative stress induced by Cd. These results provide a basis for further studies of miRNA-mediated functional adaptation of the animal to combat Cd toxicity.

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Changes in the proteome of the cadmium-tolerant bacteria Cupriavidus taiwanensis KKU2500-3 in response to cadmium toxicity

Canadian Journal of Microbiology ◽

10.1139/cjm-2013-0713 ◽

2014 ◽

Vol 60 (3) ◽

pp. 121-131 ◽

Cited By ~ 8

Author(s):

Surasak Siripornadulsil ◽

Lalita Thanwisai ◽

Wilailak Siripornadulsil

Keyword(s):

Stress Responses ◽

Cadmium Toxicity ◽

Differentially Expressed ◽

Future Application ◽

Lag Phase ◽

Cd Toxicity ◽

Differentially Expressed Protein ◽

Proteomic Approach ◽

General Response

Cupriavidus taiwanensis KKU2500-3 is a cadmium (Cd)-tolerant bacterial strain that was previously isolated from rice fields contaminated with high levels of Cd. In 500 μmol/L CdCl2, the KKU2500-3 strain grew slower and with a more prolonged lag-phase than when grown in the absence of Cd. A proteomic approach was used to characterize the protein expression in the Cd-tolerant bacteria C. taiwanensis KKU2500-3 during growth under Cd stress. When compared with the untreated cells, a total of 982 differentially expressed protein spots were observed in the CdCl2-treated cells, and 59 and 10 spots exhibited >2- and >4-fold changes, respectively. The level of up- and downregulation varied from 2.01- to 11.26-fold and from 2.01- to 5.34-fold, respectively. Of the 33 differentially expressed protein spots analyzed by MALDI TOF MS/MS, 19 spots were successfully identified, many of which were involved in stress responses. The most highly upregulated protein (+7.95-fold) identified was the chaperone GroEL, which indicated that this factor likely contributed to the bacterial survival and growth in response to Cd toxicity. Detection of the downregulated protein flagellin (–3.52-fold) was consistent with the less effective ATP-mediated and flagella-driven motility. The flagella-losing cells were also observed in the Cd-treated bacteria when analyzed by scanning electron microscopy. Thus, the Cd-stressed cells may downregulate pathways involving ATP utilization in favor of other mechanisms in response to Cd toxicity. When the KKU2500-3 strain was grown in the presence of Cd, H2S was not detected, suggesting a possible role of the sulfur in precipitation with Cd. Apart from a general response, no specific process could be determined using the present proteomic approach. However, the potential role of protein folding-mediated GroEL, flagella-mediated motility and CdS biotransformation in Cd toxicity response observed in this study as well as the extent of Cd-tolerant mechanisms using other methods could facilitate the future application of this strain in addressing Cd environmental contamination.

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Comparative Physiological and Transcriptomic Analyses Reveal Ascorbate and Glutathione Coregulation of Cadmium Toxicity Resistance in Wheat Genotypes

10.21203/rs.3.rs-696325/v1 ◽

2021 ◽

Author(s):

Tao Zhang ◽

Jingui Xiao ◽

Yongsheng Zhao ◽

Yifan Zhang ◽

Yaqi Jie ◽

...

Keyword(s):

Cadmium Toxicity ◽

Resistance Mechanism ◽

Root Growth Inhibition ◽

Cd Toxicity ◽

Wheat Genotypes ◽

Combined Application ◽

Genes Encoding ◽

Detoxification Mechanisms ◽

Classic Symptom ◽

Sensitive Genotype

Abstract Background: Understanding the cadmium (Cd) resistance mechanism is crucial for combating the phytotoxicity of Cd and meeting the increasing food demand daily. A classic symptom of Cd toxicity is root growth inhibition. Results: Using two wheat genotypes (Cd tolerant genotype T207 and Cd sensitive genotype S276) with differing root growths in response to Cd, we conducted comparative physiological and transcriptomic analyses and exogenous application tests to interpret Cd detoxification mechanisms. S276 accumulated more H2O2, O2-, and malonaldehyde than T207. Catalase activity and levels of ascorbic acid (AsA) and glutathione (GSH) were higher, whereas superoxide dismutase and peroxidase activities were lower in T207 than in S276. Transcriptome analysis showed that the expression of RBOHA, RBOHC, and RBOHE significantly increased, whereas that of RBOHB markedly decreased by Cd treatment. The transcriptional levels of 22 genes encoding RBOH were higher, and that of 11 genes were lower in T207 than in S276. The transcription of genes involved in the AsA-GSH cycle was profoundly reshaped by Cd treatment; 124 genes were higher and 43 genes were lower in T207 than in S276. Exogenous combined application of AsA and GSH alleviated Cd toxicity by scavenging excess ROS and coordinately modulating root length and branching, especially in S276.Conclusions: These results indicate that the AsA-GSH cycle fundamentally and vigorously influences plant defense against Cd toxicity, which provides valuable information for further clarification of the mechanisms underlying Cd detoxification.

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The MarR-Type Regulator PA3458 Is Involved in Osmoadaptation Control in Pseudomonas aeruginosa

International Journal of Molecular Sciences ◽

10.3390/ijms22083982 ◽

2021 ◽

Vol 22 (8) ◽

pp. 3982

Author(s):

Karolina Kotecka ◽

Adam Kawalek ◽

Kamil Kobylecki ◽

Aneta Agnieszka Bartosik

Keyword(s):

Pseudomonas Aeruginosa ◽

Binding Sites ◽

Transcriptional Profiling ◽

Mrna Level ◽

Transcriptional Regulators ◽

Resistance Mechanisms ◽

Chronic Infections ◽

Environmental Signals ◽

Regulatory Systems

Pseudomonas aeruginosa is a facultative human pathogen, causing acute and chronic infections that are especially dangerous for immunocompromised patients. The eradication of P. aeruginosa is difficult due to its intrinsic antibiotic resistance mechanisms, high adaptability, and genetic plasticity. The bacterium possesses multilevel regulatory systems engaging a huge repertoire of transcriptional regulators (TRs). Among these, the MarR family encompasses a number of proteins, mainly acting as repressors, which are involved in response to various environmental signals. In this work, we aimed to decipher the role of PA3458, a putative MarR-type TR from P. aeruginosa. Transcriptional profiling of P. aeruginosa PAO1161 overexpressing PA3458 showed changes in the mRNA level of 133 genes; among them, 100 were down-regulated, suggesting the repressor function of PA3458. Concomitantly, ChIP-seq analysis identified more than 300 PA3458 binding sites in P. aeruginosa. The PA3458 regulon encompasses genes involved in stress response, including the PA3459–PA3461 operon, which is divergent to PA3458. This operon encodes an asparagine synthase, a GNAT-family acetyltransferase, and a glutamyl aminopeptidase engaged in the production of N-acetylglutaminylglutamine amide (NAGGN), which is a potent bacterial osmoprotectant. We showed that PA3458-mediated control of PA3459–PA3461 expression is required for the adaptation of P. aeruginosa growth in high osmolarity. Overall, our data indicate that PA3458 plays a role in osmoadaptation control in P. aeruginosa.

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Transcriptional profiling of differentially expressed long non-coding RNAs in breast cancer

Genomics Data ◽

10.1016/j.gdata.2015.09.020 ◽

2015 ◽

Vol 6 ◽

pp. 214-216 ◽

Cited By ~ 1

Author(s):

Lizhen Wang ◽

Xiaokun Shen ◽

Bojian Xie ◽

Zhaosheng Ma ◽

Xiaobing Chen ◽

...

Keyword(s):

Breast Cancer ◽

Transcriptional Profiling ◽

Differentially Expressed ◽

Non Coding Rnas

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Effect of manganese on cadmium toxicity in maize seedlings

Plant Soil and Environment ◽

10.17221/3358-pse ◽

2011 ◽

Vol 52 (No. 4) ◽

pp. 143-149 ◽

Cited By ~ 21

Author(s):

P. Paľove-Balang ◽

A. Kisová ◽

J. Pavlovkin ◽

MistríkI

Keyword(s):

Root Growth ◽

Nitrate Uptake ◽

Reductase Activity ◽

Cadmium Toxicity ◽

Uptake System ◽

Maize Seedlings ◽

Cd Toxicity ◽

Maize Plants ◽

Pre Treatment ◽

Free Media

The interaction of manganese with cadmium (Cd) toxicity was studied on maize plants grown in hydroponics. Manganese supplied as MnSO<sub>4</sub>clearly alleviated the toxic effect of cadmium on the root growth of maize seedlings. The magnitude of alleviation was dose dependant and total abolition of 10µM Cd toxicity on root growth was observed at Mn/Cd ratio of 20:1. The 12 h pre-treatment with 10μM Cd was generally toxic for nitrate uptake and reduction (both determined in Cd-free media). The beneficial effect of 100μM Mn on this toxicity was confirmed for the low-affinity nitrate uptake system, but on the other hand, Mn alone seems to be slightly toxic for high affinity nitrate uptake system and on the nitrate reductase activity.

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Transcriptome Analysis of Sorbic Acid-Stressed Bacillus subtilis Reveals a Nutrient Limitation Response and Indicates Plasma Membrane Remodeling

Journal of Bacteriology ◽

10.1128/jb.01516-07 ◽

2007 ◽

Vol 190 (5) ◽

pp. 1751-1761 ◽

Cited By ~ 45

Author(s):

Alex Ter Beek ◽

Bart J. F. Keijser ◽

Andre Boorsma ◽

Anna Zakrzewska ◽

Rick Orij ◽

...

Keyword(s):

Bacillus Subtilis ◽

Plasma Membrane ◽

Nutrient Limitation ◽

Fatty Acid Biosynthesis ◽

Sorbic Acid ◽

Tricarboxylic Acid Cycle ◽

Transcriptional Profiling ◽

Acid Stress ◽

Resistance Mechanisms ◽

Membrane Remodeling

ABSTRACT The weak organic acid sorbic acid is a commonly used food preservative, as it inhibits the growth of bacteria, yeasts, and molds. We have used genome-wide transcriptional profiling of Bacillus subtilis cells during mild sorbic acid stress to reveal the growth-inhibitory activity of this preservative and to identify potential resistance mechanisms. Our analysis demonstrated that sorbic acid-stressed cells induce responses normally seen upon nutrient limitation. This is indicated by the strong derepression of the CcpA, CodY, and Fur regulon and the induction of tricarboxylic acid cycle genes, SigL- and SigH-mediated genes, and the stringent response. Intriguingly, these conditions did not lead to the activation of sporulation, competence, or the general stress response. The fatty acid biosynthesis (fab) genes and BkdR-regulated genes are upregulated, which may indicate plasma membrane remodeling. This was further supported by the reduced sensitivity toward the fab inhibitor cerulenin upon sorbic acid stress. We are the first to present a comprehensive analysis of the transcriptional response of B. subtilis to sorbic acid stress.

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Differential Potential of Phytophthora capsici Resistance Mechanisms to the Fungicide Metalaxyl in Peppers

Microorganisms ◽

10.3390/microorganisms8020278 ◽

2020 ◽

Vol 8 (2) ◽

pp. 278 ◽

Cited By ~ 1

Author(s):

Weiyan Wang ◽

Xiao Liu ◽

Tao Han ◽

Kunyuan Li ◽

Yang Qu ◽

...

Keyword(s):

Mutant Strain ◽

Differentially Expressed Genes ◽

Phytophthora Capsici ◽

Resistance Mechanism ◽

Resistant Mutant ◽

Resistance Mechanisms ◽

Differentially Expressed ◽

Pathogenicity Test ◽

Wild Type ◽

Metalaxyl Resistance

Metalaxyl is one of the main fungicides used to control pepper blight caused by Phytophthora capsici. Metalaxyl resistance of P. capsici, caused by the long-term intense use of this fungicide, has become one of the most serious challenges facing pest management. To reveal the potential resistance mechanism of P. capsici to fungicide metalaxyl, a metalaxyl-resistant mutant strain SD1-9 was obtained under laboratory conditions. The pathogenicity test showed that mutant strain SD1-9 had different pathogenicity to different host plants with or without the treatment of metalaxyl compared with that of the wild type SD1. Comparative transcriptome sequencing of mutant strain SD1-9 and wild type SD1 led to the identification of 3845 differentially expressed genes, among them, 517 genes were upregulated, while 3328 genes were down-regulated in SD1-9 compared to that in the SD1. The expression levels of 10 genes were further verified by real-time RT-PCR. KEGG analysis showed that the differentially expressed genes were enriched in the peroxisome, endocytosis, alanine and tyrosine metabolism. The expression of the candidate gene XLOC_020226 during 10 life history stages was further studied, the results showed that expression level reached a maximum at the zoospores stage and basically showed a gradually increasing trend with increasing infection time in pepper leaves in SD1-9 strain, while its expression gradually increased in the SD1 strain throughout the 10 stages, indicated that XLOC_020226 may be related to the growth and pathogenicity of P. capsici. In summary, transcriptome analysis of plant pathogen P. capsici strains with different metalaxyl resistance not only provided database of the genes involved in the metalaxyl resistance of P. capsici, but also allowed us to gain novel insights into the potential resistance mechanism of P. capsici to metalaxyl in peppers.

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Effects of exogenous nitric oxide on cadmium toxicity in black poplar (Populus nigra): physiological approaches

Acta Botanica Croatica ◽

10.2478/botcro-2019-0018 ◽

2019 ◽

Vol 78 (2) ◽

pp. 116-124 ◽

Cited By ~ 1

Author(s):

Yakup Cikili ◽

Semsettin Kulac ◽

Halil Samet ◽

Ertugrul Filiz

Keyword(s):

Nitric Oxide ◽

Plant Biomass ◽

Cadmium Toxicity ◽

Populus Nigra ◽

No Donor ◽

Cd Toxicity ◽

Physiological Processes ◽

Black Poplar ◽

Randomized Design ◽

Metallic Contaminant

Abstract Cadmium (Cd) is a highly toxic metallic contaminant that negatively affects plant metabolism and causes reductions in productivity. Nitric oxide (NO) is a signaling molecule that regulates various physiological processes and is involved in response to biotic/abiotic stresses. This work investigated the effects of exogenous sodium nitroprusside (SNP), a nitric oxide (NO) donor, application on Cd toxicity in black poplar (Populus nigra). Black poplars were exposed to individual/combined CdCl2 and SNP treatments for 21 days by complete randomized design with three replications. Cd concentrations increased in leaves, bark, and roots at Cd treatments, whereas Cd + SNP applications had alleviative effects on Cd exposures, except for leaves. Photosynthetic pigments (chlorophyll a, b, a + b and carotenoids) reduced with Cd treatments in leaves, while they increased in Cd + SNP applications. Similarly, plant biomass was reduced with Cd treatments, but Cd + SNP application prevented these reductions. SNP also alleviated malondialdehyde (MDA) and hydrogen peroxide (H2O2) accumulation in leaves under Cd treatments. Catalase (CAT, EC 1.11.1.6) and ascorbate peroxidase (APX, EC 1.11.1.11) activities were also affected by Cd and Cd + SNP applications. Cd exposure also decreased Zn2+, Fe2+ and Mn2+ levels in leaves, bark and roots, while it increased Cu2+ level in leaves and roots. This study concludes that Cd toxicity caused a reduction of plant growth and mineral nutrition parameters. However, SNP indicates great potentials for improving the growth under Cd toxicity in P. nigra.

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