Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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Changes in Arabidopsis thaliana gene expression in response to silver nanoparticles and silver ions

ABSTRACT: The release of silver nanoparticles (SNPs) in the environment has raised concerns about their effects on living organisms, including plants. In this study, changes in gene expression in Arabidopsis thaliana exposed to SNPs and silver ions (Ag+) were analyzed using Affymetrix expression microarrays. Exposure to 5 mg SNPs L-1 (20 nm) for 10 days resulted in up-regulation of 286 genes and down-regulation of 81 genes by reference to non-exposed plants. Exposure to 5 mg Ag+ L-1 for 10 days resulted in up-regulation of 84 genes and down-regulation of 53 genes by reference to non-exposed plants. Many genes differentially expressed by SNPs and Ag+ were found to be involved in plant response to various stresses: up-regulated genes were primarily associated with response to metals and oxidative stress (e.g., vacuolar cation/proton exchanger, superoxide dismutase, cytochrome P-450-dependent oxidase, and peroxidase), while down-regulated genes were more associated with response to pathogens and hormonal stimuli (e.g., auxin-regulated gene involved in organ size (ARGOS), ethylene signaling pathway, and systemic acquired resistance (SAR) against fungi and bacteria). A significant overlap was observed between genes differentially expressed in response to SNPs and Ag+ (13% and 21% of total up- and down-regulated genes, respectively), suggesting that SNP-induced stress originates partly from silver toxicity and partly from nanoparticle-specific effects. Three highly up-regulated genes in the presence of SNPs, but not Ag+, belong to the thalianol biosynthetic pathway, which is thought to be involved in plant defense system. Results from this study provide insights into the molecular mechanisms of plant response to SNPs and Ag+.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Benoit Van Aken

PROVIDER: E-MEXP-3950 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Changes in Arabidopsis thaliana gene expression in response to silver nanoparticles and silver ions.

Kaveh Rashid R Li Yue-Sheng YS Ranjbar Sibia S Tehrani Rouzbeh R Brueck Christopher L CL Van Aken Benoit B

Environmental science & technology 20130909 18

The release of silver nanoparticles (AgNPs) in the environment has raised concerns about their effects on living organisms, including plants. In this study, changes in gene expression in Arabidopsis thaliana exposed to polyvinylpyrrolidone-coated AgNPs and silver ions (Ag(+)) were analyzed using Affymetrix expression microarrays. Exposure to 5 mg/L AgNPs (20 nm) for 10 days resulted in upregulation of 286 genes and downregulation of 81 genes by reference to nonexposed plants. Exposure to 5 mg/L ...[more]

PMID: 23962165

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Changes in Arabidopsis thaliana gene expression in response to silver nanoparticles and silver ions

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Changes in Arabidopsis thaliana gene expression in response to silver nanoparticles and silver ions.

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