Project description:Duckweeds are small, rapidly growing aquatic flowering plants. Due to their ability for biomass production at high rates they represent promising candidates for biofuel feedstocks. Duckweeds are also excellent model organisms because they can be maintained in well-defined liquid media, usually reproduce asexually, and because genomic resources are becoming increasingly available. To establish a framework for quantitative metabolic research in duckweeds we derived a central carbon metabolism network model of Lemna gibba based on its draft genome. Lemna gibba fronds were grown in a photomixotrophic mode in liquid media under continuous light with 13C-labeled glucose as a carbon source. Two different conditions (nitrate vs. glutamine as nitrogen source) were compared by quantification of growth kinetics, metabolite levels, metabolic flux and transcript abundance.
Project description:The experiment investigates how the artificial sweetener sucralose affects gene expression in the teleost fish Danio rerio in order to derive mechanistic information relevant for environmental risk assessment. The main test including transcriptomics, was conducted with 10 µg/L and 100 mg/L as test concentrations. Whole plant tissue from each exposure group and corresponding controls was sampled after 7 days for RNA extraction, and poly(A)-enriched RNA was sequenced (paired-end, 150 bp) on an Illumina NovaSeq platform, followed by alignment to the Lemna minor reference genome and differential expression analysis using a DESeq2-based workflow with independent hypothesis weighting, data-driven log2 fold-change thresholds, and multiple-testing correction to define robust sets of differentially expressed genes per substance and concentration. Overrepresentation analysis of Gene Ontology terms using a common detected-gene background then mapped these gene-level changes to biological processes.
Project description:Lemna minor a small aquatic plant has been used extensively in ecotoxicolgical testing to elucidate substance-related effects to freshwater plants. They are free-floating freshwater macrophyte, very sensitive towards chemical exposure and easy to cultivate thus makes the plant suitable for laboratory testing. Here we present a rapid and reproducible data dependent proteomics approach for identifying growth related molecular signatures in lemna minor as an alternative to algae testing. For this, we have analyzed the proteome of lemna minor exposed to bentazon as a model substances for identifying growth related molecular perturbations. These fingerprints allow for a definition of potential biomarkers as tools in screening approaches and for integration in plant growth inhibition studies, for identifying suspect substances, such as in the Lemna sp. growth inhibition test (OECD TG 221).
