bioavailability,; ecotoxicogenomics; macrophyte; microalgae
Dranguet Perrine, Flueck Rebecca, Regier Nicole, Le Faucheur Severine, Cosio Claudia, Slaveykova Vera (2014), Towards mechanistic understanding of mercury availability and toxicity to aquatic primary producers, in Chimia
, 68, 799-805.
Larras Florianne, Regier Nicole, Planchon Sébastien, Poté John, Renaut Jenny, Cosio Claudia (2013), Physiological and proteomic changes in shoots of Elodea nuttallii suggest an important role of cell walls in its high tolerance to Hg and Cd, in Journal of Hazardous Materials
Regier Nicole, Frey Beat, Converse Brandon, Roden Eric, Grosse-Honebrink Alexander, Garcia Bravo Andrea, Cosio Claudia (2012), Elodea nuttallii roots effect on bacterial communities and MMHg proportion in an Hg polluted sediment, in Plos one
, 7(9), e45565.
Cosio Claudia, Flueck Rebecca, Regier Nicole, Slaveykova Vera, Effects of macrophytes on the fate of mercury in aquatic systems., in Environmental Toxicology and Chemistry
Contamination in surface water remains of concern in many sites, despite considerable efforts and investments in wastewater treatment and in prevention of emissions. In this context ecotoxicology - the study of organism’s response to toxicants- is used as a tool to predict the effects of pollution so that the most efficient action can be identified for management of ecosystems. Being able to measure bioavailability to organisms accurately is perceived to play a major role to successful attainment of this goal. Indeed, the bioavailability concepts originates from the fact that detrimental effects in exposed organisms are not caused by the entire amount of chemical compounds present in the environment but only by the fraction that is taken up by the organisms.The proposed project aims to assess the relationship between toxic metal bioavailability and expression of genes in two representative aquatic primary producers: a rooted macrophyte and a green microalgae, representing the aquatic plants and the phytoplankton typically found in the benthic environment and the water column. This difference in the habitat creates substantial differences with respect to the amount and exposure length of trace metals. Bioavailability of Cu and two speciation of Hg (inorganic HgCl2 and organic CH3HgCl) will be compared to transcriptome modifications analyzed by RNAseq as well as other endpoints including growth and photosynthesis in each organism. Bioavailability will be determined by measurement of the adsorbed and internalized metal concentrations at different exposure times. The specificity of the gene response to each toxicant and the response to their mixtures will be assessed. Genes identified in both organisms in similar conditions will be compared to determine how similar are primary producers’ response to heavy metals.The proposed approaches will contribute to improve our understanding of bioavailability and detrimental effects of metals to aquatic primary producers. In particular mode of action and uptake of Cu and Hg will be studied and compared in microalgae and macrophyte. Ecotoxicogenomics has been rarely applied to primary producers until now, moreover macrophytes. This fundamental knowledge might help to develop new tools for the field of ecotoxicology. Indeed, ecotoxicogenomics present exciting opportunities for improved methods of identifying and evaluating potential environmental toxicants, as well as to evaluate their bioavailability and monitoring the effects of exposures to these toxicants.