Project description:The pollution of the environment with microplastics has been recognized as an emerging threat worldwide. Due to an exponential increase in production of plastic over the last eight decades and its longevity in the environment, accumulating amounts of microplastic are polluting rivers, lakes and the ocean. Their entry pathways are diverse and still only incompletely understood. Since microplastics are usually defined smaller than 5 mm, it can be ingested by a wide range of aquatic organisms including teleost fish. There are different approaches to study the detrimental effects of pollutants on aquatic organisms. On the one hand, generic baseline parameters such as growth and mortality are regularly considered, often accompanied by established stress parameters such as cortisol, heat shock proteins or lipid oxidation. The conflicting findings to date suggest that these parameters might not be sensitive enough to indicate the physiological effects of environmentally relevant microplastic concentrations. For this reason, more sophisticated biological approaches could provide new insights into whether and how microplastics harm fish. To date, proteomic approaches have been used only sporadically when investigating the effects of microplastic exposure on aquatic organisms. So far, this approach has not been used to address potential microplastic impacts in fish. In the present study, a proteomic approach was trialed alongside established methods in an investigation of fish experiencing long-term exposure to environmentally relevant concentrations of microplastics. Two groups of rainbow trout (Oncorhynchus mykiss were exposed to microplastic concentrations and sizes currently encountered in wild fish and an increased concentration, expected to occur in the near future. These groups where compared to a control group maintained in MP free conditions. Five fish of each treatment were sampled at three time points (week 1, week 4, week 17). The experiments were performed in triplicates, resulting in 45 samples used in the proteomic analysis.
Project description:Cellular uptake and cytotoxicity data from neural cells treated with microplastics were compared and contrasted. Transcriptomic data obtained by RNA-seq from astrocytes treated with microplastics was assessed further.
Project description:Microplastics represent a growing environmental concern for the oceans due to their potential capability to adsorb different classes of pollutants, thus representing a still unexplored source of exposure for aquatic organisms. In this study polystyrene (PS) microplastics were characterized for their capability to adsorb pyrene (PYR) as model compound for polycyclic aromatic hydrocarbons, and transfer this chemical to filter feeding mussels Mytilus galloprovincialis. Gene expression analyses of Mytilus galloprovincialis exposed to polystyrene (PS) microplastics and to polystyrene contaminated with pyrene (PS-PYR) have been performed trough a DNA microarray platform.
2014-12-27 | GSE57460 | GEO
Project description:Aquatic prokaryotic microorganism in microcosm experiment
Project description:In a manner similar to ubiquitin, the prokaryotic ubiquitin-like protein (Pup) has been shown to target proteins for degradation via the proteasome in mycobacteria. However, not all actinobacteria possessing the Pup protein also harbor a proteasome, suggesting fates for pupylated proteins other than degradation via a proteasome or degradation at all. In the present study we set out to study pupylation in the proteasome-lacking non-pathogenic model microorganism and biotechnological workhorse Corynebacterium glutamicum. A defined pup deletion mutant of C. glutamicum ATCC 13032 grew as the control indicating that pupylation seems to be dispensable under the conditions tested. By expression of homologous Pup carrying a poly-histidine tag in C. glutamicum ATCC 13032 we purified the first pupylome of a microorganism lacking a proteasome. Multidimensional Protein Identification Technology (MudPIT) unraveled 54 proteins being pupylated in this organism. Similar to mycobacteria, the majority of pupylated proteins in C. glutamicum can be classified as enzymes of the metabolism or as involved in translation. These results help to elucidate the common target pathways of pupylation in bacteria.
Project description:This study used an emerging analytical technology (cDNA microarrays) to assess the potential effects of PFC exposure on largemouth bass in TCMA lakes. Microarrays simultaneously measure the expression of thousands of genes in various tissues from organisms exposed to different environmental conditions. From this large data set, biomarkers (i.e., genes that are expressed in response to an exposure to known stressors) and bioindicators (e.g., suites of genes that correspond to changes in organism health) can be simultaneously measured to clarify the relationship between contaminant exposure and organism health. Based on current scientific literature, we hypothesized that gene expression patterns would be altered in fish exposed to PFCs (as compared with fish from reference lakes), and that the magnitude of these changes would correspond to the concentrations of PFCs present throughout TCMA lakes. Patterns of gene expression in largemouth bass observed across the TCMA lakes corresponded closely with PFC concentration. Concentrations of PFCs in largemouth bass varied significantly across the sampled lakes, where the lowest concentrations were found in Steiger and Upper Prior Lakes and the highest concentrations were found in Calhoun and Twin Lakes. Patterns of gene expression were most different (relative to controls) in fish with the highest PFC tissue concentrations, where fish from Twin and Calhoun Lakes were observed to have between 5437 and 5936 differentially expressed genes in liver and gonad tissues. Although gene expression patterns demonstrated a high degree of correlation with PFC concentrations, microarray data also suggest there are likely additional factors influencing gene expression patterns in largemouth bass in TCMA lakes.