Franco-Brazilian PhD co-tutelle 2020 : co-fundings of PhD co-tutelles for Brazilian PhD students (deadline 16th of March)
Postdoc Ifremer 2020_Toxicity of microalgae & cell culture
******************************** English version ********************************
Postdoctoral Researcher (18 months) at IFREMER, Concarneau, France.
Toxicity assessment of marine microalgae to fish and shellfish using cell culture
We are seeking a talented candidate to join our team specialized in marine microalgae toxicity and taxonomy. This postdoctoral project aims to determine toxicity and mode of action of marine microalgae to fish and shellfish, using bioassays targeting cultured cells. It is part of a research project studying the relationships between ichthyotoxicity, chemodiversity and genetic diversity of marine microalgae in France, involving biologists, chemists and bioinformaticians.
Key words: cell culture, bioassays, toxic microalgae, marine molluscs, fish.
Duration: 18 months, starting in 2020 (preferably June)
Location: IFREMER (French Research Institute for Exploitation of the Sea, https://wwz.ifremer.fr/en/), at the Environment & Resources Laboratory of Western Brittany (LER-BO) located in the Concarneau marine station (Concarneau, France)
Supervisors: Malwenn Lassudrie (IFREMER LER-BO) and Stéphanie Auzoux-Bordenave (UPMC-MNHN)
Harmful Algal Blooms (HABs) occur worldwide, affecting the ecology of coastal ecosystems and associated socio-economical activities. Among them, ichthyotoxic microalgae can cause marine organism mortalities and lead to considerable economic loss in the fish and shellfish industry (e.g. Chili 800M$ in 2016). In France, dinoflagellates from the Kareniacea family, known to be ichthyotoxic, are regularly observed (Nézan et al. 2014). Mortality events, recruitment and growth failures in fish and shellfish were observed on the French coast following blooms of Karenia and Karlodinium spp. (Chauvaud et al. 1998; Paulmier et al. 1995). The toxins responsible for these effects and their mode of action are still not well characterized. In other countries, fish affected by these microalgae genera display severe gill alterations associated to impaired respiration that can lead to death.
Ichthyotoxic activity is generally identified from lytic and cytotoxic properties of microalgae, measured using cellular bioassays that are more ethical and simpler to perform than in vivo assays. They target marine fish blood cells or freshwater fish gill cells (Dorantes-Aranda et al. 2011; Eschbach et al. 2001). Considering the effects observed in situ, the most relevant target cells are gill cells, ideally from marine fish and mollusc models. However, immortal gill cell lines from marine fish and molluscs are not available. Primary gill cell cultures of marine fish and molluscs, already used before in ecotoxicological studies (Avella et al. 1994; Gaume et al. 2012), would allow to reach a more realistic understanding of the effects of ichthyotoxic microalgae upon marine resources.
The aim of this project is to characterize the ichthyotoxic activity of French microalgae from the Kareniacea family, and therefore determining the risque they pose for marine resources, by answering two main questions :
1) Which species of French kareniacean can alter marine fish and mollusc gills and what is the inter- and intraspecific variability of their bioactivity ?
2) What are the mode of action of these microalgae on gill cells?
To answer these questions, this postdoctoral project proposes to :
– Work on a trout gill cell line (RTgill-W1, routinely maintained in the laboratory), and establish primary gill cell cultures of marine fish and shellfish following methods described in the literature.- Study the ichthyotoxic mode of action of microalgal cultures or extracts using bioassays targeting gill cells. Approaches combining viability assays, simultaneous analyses of several phenotypic and metabolic variables at cellular level (High Content Analysis imagery system), and study of membrane permeability, will be considered.
In parallel to the research activites, the postdoctoral researcher will have the opportunity to participate in scientific outreach, science and society activities, etc, that are organized by Ifremer or by the Concarneau marine station.
This project involves several French partners: MNHN (Concarneau marine station), LEMAR (Plouzané), IFREMER PHYC (Nantes), ANSES (Fougères), Tinduff hatchery (Plougastel), local associations for scientific outreach. Occasional visits to these different collaborators are expected.
IFREMER LER-BO and the partner laboratories will offer scientific and technical support (toxic microalgae culture and taxonomy, algal toxin analysis, cell culture in marine mollusc models), as well as acces to facilities for cellular biology, including microbiological safety cabinet, cell culture chambers, flow cytometers, epifluorescent microscopes, scanning electron microscope, High Content Analysis (HCA) imagery system.
PhD in Biology
Essential skills :
– Animal cell culture
– Cellular bioassays
– Experience in eco-toxicology or toxicology
– Statistical analyses
– Excellent oral and writing skills in English
– Autonomy and team work ability
– Experience with marine models (molluscs, fish, microalgae)
– Knowledge in physiology of marine microalgae
– Interest for scientific outreach, citizen science activities, etc.
Eligibility criteria (required from the funding agencies, région Bretagne and CD29 and intended to increase international exchanges):
The candidate must have spent at least 18 months out from France between May 1st 2016 and the beginning of the project. He/she should have completed his/her PhD for no more than 4 years, out from Bretagne and Pays de la Loire regions in France.
Benefits: Many social benefits (family, sport, culture, holidays etc) are available to IFREMER employees.
Applications should be sent before March 1st, 2020, to firstname.lastname@example.org and email@example.com, and include:
– a covering letter stating the reason and suitability for applying for this position,
– a full curriculum vitae,
– the names and contact details of three referees
Informal enquiries may be made to Malwenn Lassudrie firstname.lastname@example.org.