Project description:Classical ecotoxicological test and high-throughput molecular tools (microarray) were conducted on C. elegans to assess the effectiveness and ecosafety of a nanoremediation strategy applied to a highly polluted soil environment with heavy metals (HMs). We stablished a profiled gene expression in C. elegans exposed to the polluted soil, treated and untreated with nZVI. The results obtained showed that the percentage of differentially expressed genes decreased with the exposure time to nZVI. The expression profile of genes associated with stress response, metal toxicity, proteolysis, immune response, and cuticle development resulted affected. At short term, when a more effective HMs immobilization has occurred genes related to specific heavy metal detoxification mechanisms or to response to metal stress, were down regulated. After longer exposure time, we found decreased effectiveness of nZVI and increased HMs toxicity, whereas the transcriptional oxidative and metal-induced responses were attenuated.
Project description:Background: The high number of heavy metal resistance genes in the soil bacterium Cupriavidus metallidurans CH34 makes it an interesting model organism to study microbial responses to heavy metals. Results: In this study the transcriptional response of this bacterium was measured after challenging it to a wide range of sub-lethal concentrations of various essential or toxic metals. Considering the global transcriptional responses for each challenge as well as by identifying the overlap in upregulated genes between different metal responses, the sixteen metals could be clustered in three different groups. Additionally, next to the assessment of the transcriptional response of already known metal resistance genes, new metal response gene clusters were identified. The majority of the metal response loci showed similar expression profiles when cells were exposed to different metals, suggesting complex cross-talk at transcriptional level between the different metal responses. The highly redundant nature of these metal resistant regions – illustrated by the large number of paralogous genes – combined with the phylogenetic distribution of these metal response regions within evolutionary related and other metal resistant bacteria, provides important insights on the recent evolution of this naturally soil dwelling bacterium towards a highly metal-resistant strain found in harsh and anthropogenic environments. Conclusions: The metal-resistant soil bacterium Cupriavidus metallidurans CH34 displays myriads of gene expression patterns when exposed to a wide range of heavy metals at non-lethal concentrations. The interplay between the different gene expression clusters points towards a complex cross-regulated regulatory network governing heavy metal resistance in C. metallidurans CH34. Keywords: Cupriavidus metallidurans CH34, transcriptional regulation, heavy metal resistance
Project description:Background: The high number of heavy metal resistance genes in the soil bacterium Cupriavidus metallidurans CH34 makes it an interesting model organism to study microbial responses to heavy metals. Results: In this study the transcriptional response of this bacterium was measured after challenging it to a wide range of sub-lethal concentrations of various essential or toxic metals. Considering the global transcriptional responses for each challenge as well as by identifying the overlap in upregulated genes between different metal responses, the sixteen metals could be clustered in three different groups. Additionally, next to the assessment of the transcriptional response of already known metal resistance genes, new metal response gene clusters were identified. The majority of the metal response loci showed similar expression profiles when cells were exposed to different metals, suggesting complex cross-talk at transcriptional level between the different metal responses. The highly redundant nature of these metal resistant regions – illustrated by the large number of paralogous genes – combined with the phylogenetic distribution of these metal response regions within evolutionary related and other metal resistant bacteria, provides important insights on the recent evolution of this naturally soil dwelling bacterium towards a highly metal-resistant strain found in harsh and anthropogenic environments. Conclusions: The metal-resistant soil bacterium Cupriavidus metallidurans CH34 displays myriads of gene expression patterns when exposed to a wide range of heavy metals at non-lethal concentrations. The interplay between the different gene expression clusters points towards a complex cross-regulated regulatory network governing heavy metal resistance in C. metallidurans CH34. Keywords: Cupriavidus metallidurans CH34, transcriptional regulation, heavy metal resistance Two-condition experiments. Comparing samples after induction with heavy metals versus non-induced samples. Biological duplicate or triplicate. Each array contains 3 or 4 technical replicates.
Project description:Heavy metals are essential integral parts of cells and environmental toxicants, whose deregulation is associated with severe cellular dysfunction and various diseases. The Hippo pathway plays a critical role in organ size control and cancer development. In this study, we use RNA-Seq to investigate the role of the Hippo pathway in regulating heavy metal response gene transcription. Specifically, the difference of transcriptional profiles between the wild-type and the Hippo pathway kinases LATS1/2-deficient HEK293A cells was examined under control- and heavy metals zinc and cadimuim treated-conditions.
Project description:Transcriptome changes associated with metal stress were investigated in order to identify tolerance mechanisms and the impact on inositol signaling. The wild type S. commune 12-43 was compared with 12-43 grown with addition of contaminated seepage water (HSW) and another wild type strain W22 grown with 0.01 mM Cd.
Project description:The mechanisms of heavy metal accumulation in primary producers and the damage and stress response induced by heavy metals is not well understood. We used UHTS to analyze the transcriptomic response of Elodea nuttallii to heavy metal pollution. We exposed shoots of E. nuttallii for 24 h to increasing concentrations of Hg and Cd. Using Illumina RNA-Seq, we have generated over 50 million 54 nt paired end reads and 14 million single end reads, which we used for de novo assembly of the E. nuttallii transcriptome.