Marine Symbiosis

Study of the Cnidarian-Dinoflagellate marine symbiosis.

Symbiotic cnidarians (corals, sea fans and sea anemones) live in symbiosis with micro-algae, which are photosynthetic dinoflagellates, called zooxanthellae. This mutualistic relationship has advantages, mainly concerning trophic exchanges, but also constraints, requiring the establishment of a true molecular dialogue between the two partners. In case of environmental stresses, the symbiosis may be broken, the loss of algae leading to the invertebrate bleaching. 

Chronically, this can lead to the death of affected animals and therefore to the entire associated ecosystem. Better understanding the mechanisms of establishment, maintain and break-donw of this association is at the heart of our multidisciplinary research (from genes to populations) carried out mainly on organisms of the temperate waters of the Mediterranean Sea.

The sea anemone, Anemonia viridis, is our main biological model of marine symbiosis allowing us to demonstrate several strategies to adapt to symbiosis and the involvement of various cellular processes such as oxidative stress and apoptotic cascades in the induction of bleaching. Using transcriptomic (DNA microarray) and proteomics approaches, we tend to understand more generally the molecular dialogue between the two partners. In addition, host/symbiont genetic diversity and its relationship with local adaptation are also studied throughout the Mediterranean basin. 

Finally, we recently developed cell cultures from sea anemone, to explore the mechanisms of symbiosis at the cellular level.