Project description:Changes in soil properties (e.g. pH, organic matter content, granulometry) can influence chemical toxicity to organisms and act alone as stressors. Previous studies on Enchytraeus albidus showed that changes in soil properties caused effects on reproduction and avoidance behavior and also oxidative stress. In addition, results at the transcritptomic level indicated changes in gene expression profile due to soil properties changes. In this study, E. albidus was exposed to modified versions of the artificial standard OECD soil (different pH, OM and clay content) in different exposure times (2, 4 and 8 days). The gene expression profile was characterized using a class comparison statistical analysis. Results indicated that the transcriptional response was time dependent, with different genes being affected at different time points. Results also showed some genes (and biological functions) being affected in a soil specific way.
Project description:Changes in soil properties (e.g. pH, organic matter content, granulometry) can influence chemical toxicity to organisms and act alone as stressors. Previous studies on Enchytraeus albidus showed that changes in soil properties caused effects on reproduction and avoidance behavior and also oxidative stress. In addition, results at the transcritptomic level indicated changes in gene expression profile due to soil properties changes. In this study, E. albidus was exposed to modified versions of the artificial standard OECD soil (different pH, OM and clay content) in different exposure times (2, 4 and 8 days). The gene expression profile was characterized using a class comparison statistical analysis. Results indicated that the transcriptional response was time dependent, with different genes being affected at different time points. Results also showed some genes (and biological functions) being affected in a soil specific way. Fluorescently labelled cDNA, from enchytraeids exposed during 2, 4 and 8 days OECD standard soil (Cy3) and to the different exposure conditions (modified OECD soil) (Cy5), was synthesized for microarray analysis and hybridizations were performed. After scanning (Agilent Microarray Scanner from Agilent Technologies), spots were identified and ratios quantified using Quantarray (Packard Biochip Technologies). Statistical analysis of the microarrays was performed using BRB Array Tools version 3.8.1 Stable Release (http://linus.nci.nih.gov/BRB-ArrayTools.html). After background subtraction, the replicated spots within each array were averaged, and microarrays were normalized using loess method (Smith and Speed, 2003). Statistical class comparison between groups of arrays was performed between each exposure condition and the respective “control” (exposure in OECD standard soil, for each time of exposure) using two-sample T-test and 95% of confidence level for the assessment of differentially expressed genes.
Project description:Plant can perceive and respond natural sound vibration (SV). Artificial SV also served as a novel trigger of induced resistance, although approaches for activating such plant innate immunity intensively studied on the use of biological and chemical agents (BCA). Artificial SV pre-treatment protected Arabidopsis thaliana seedlings against insect pests and fungal pathogens. However, SV-mediated epigenetic modulation remains unexplored while CBA-mediated induced resistance is known as a complicated process involving epigenetic regulation. Here, we performed a ChIP-seq analysis to understand the role of 10 kHz SV-mediated epigenetic modification in induced resistance against a soil-borne pathogenic bacterium Ralstonia solanacearum.
Project description:The melting of permafrost and its potential impact on greenhouse gas emissions is a major concern in the context of global warming. The fate of the carbon trapped in permafrost will largely depend on soil physico-chemical characteristics, among which are the quality and quantity of organic matter, pH and water content, and on microbial community composition. In this study, we used microarrays and real-time PCR (qPCR) targeting 16S rRNA genes to characterize the bacterial communities in three different soil types representative of various Arctic settings. The microbiological data were linked to soil physico-chemical characteristics and CO2 production rates. Microarray results indicated that soil characteristics, and especially the soil pH, were important parameters in structuring the bacterial communities at the genera/species levels. Shifts in community structure were also visible at the phyla/class levels, with the soil CO2 production rate being positively correlated to the relative abundance of the Alphaproteobacteria, Bacteroidetes, and Betaproteobacteria. These results indicate that CO2 production in Arctic soils does not only depend on the environmental conditions, but also on the presence of specific groups of bacteria that have the capacity to actively degrade soil carbon.
Project description:Plant can perceive and respond natural sound vibration (SV). Artificial SV also served as a novel trigger of induced resistance, although approaches for activating such plant innate immunity intensively studied on the use of biological and chemical agents (BCA). Artificial SV pre-treatment protected Arabidopsis thaliana seedlings against insect pests and fungal pathogens. However, SV-mediated epigenetic modulation remains unexplored while CBA-mediated induced resistance is known as a complicated process involving epigenetic regulation. Here, we performed an expression profiling basd on small RNA-seq experiment to understand the role of 10 kHz SV-mediated epigenetic modification in induced resistance against a soil-borne pathogenic bacterium Ralstonia solanacearum.
Project description:We introduce Chemical-crosslinking Assisted Proximity Capture (CAP-C), a method that utilizes multi-functional chemical crosslinkers with defined physical sizes to directly assess spatial distances between nuclear genomic sequences. CAP-C avoids limitations caused by extensive protein-DNA crosslinking in most in situ methods, and thus generates chromatin contact maps at high resolution with low background noise.
Project description:Cyanobacteria of biological soil crusts from Brazilian dry tropical forest (caatinga) and southern grasslands (pampa): metagenomics, taxonomic characterization and relationships with physical and chemical parameters
Project description:This study examined how transcriptomics tools can be included in a Triad-based soil quality assessment to assess the toxicity of soils from river banks polluted by metals. To that end we measured chemical soil properties and used the standardized ISO guideline for ecotoxicological tests and a newly developed microarray for gene expression in the indicator soil arthropod, Folsomia candida. Microarray analysis revealed that the oxidative stress response pathway was significantly affected in all soils except one. The data indicate that changes in cell redox homeostasis are a significant signature of metal stress. Finally, 32 genes showed significant dose-dependent expression with metal concentrations. They are promising genetic markers providing an early indication of the need for higher tier testing in soil quality. One of the least polluted soils showed toxicity in the bioassay that could be removed by sterilization. The gene expression profile for this soil did not show a metal-related signature, confirming that another factor than metals (most likely of biological origin) caused the toxicity. This study demonstrates the feasibility and advantages of integrating transcriptomics into Triad-based soil quality assessment. Combining molecular and organismal life-history trait’s stress responses helps identifying causes of adverse effect in bioassays. Further validation is needed for verifying the set of genes with dose-dependent expression patterns linked with toxic stress.
2014-02-01 | GSE52393 | GEO
Project description:Biological treatment of chemical wastewater containing cyanide