Laminarionema elsbetiae, the endophyte Ectocarpales

My name is Maëlle Zonnequin and I’m a second-year PhD student at the Laboratory of Integrative Biology of Marine Models (LBI2M) at the Station Biologique de Roscoff. I’m particularly interested in understanding how brown algae interact with other organisms in the marine ecosystem.
Throughout evolution, biotic interactions have probably played a key role in the metabolic plasticity and adaptation of species. In my thesis, I am focusing on the function and evolutionary origin of the oxylipin pathway in biotic interactions in brown algae. More specifically, I am testing the hypothesis of functional coevolution between two closely related brown algae: a host belonging to the family Laminariales and an endophytic Ectocarpales. Their phylogenetic proximity increases the likelihood that their metabolic pathways involve orthologous enzymes with similar catalytic activities, which could in particular allow compensation phenomena leading to gene losses in the endophyte. The aim of this project is to gain a better understanding of the ecology and evolution of chemical signalling in brown algae in the context of biotic interactions.

I am very grateful to the French Phycological Society (SPF) for selecting my thesis project for a grant that will enable me to attend the 39th annual conference of the International Society for Chemical Ecology in Prague (ISCE2024) and present the progress of my thesis work from 14 to 18 July 2024.