Land plants all share a common ancestor that made the leap from water to land. This major transition, known as terrestrialization, marked a pivotal moment in plant evolution. How exactly plants adapted to life on land is still a topic of active research, but it is clear that this process led to the development of new plant metabolic pathways. These pathways evolved in different plant species over time. Two important types of molecules that helped plants adapt to land are phenylpropanoids and apo-carotenoids derived molecules. Phenylpropanoids play a key role in protecting plants from harmful UV rays and serve as building blocks for plant cell structures. Apo-carotenoids, on the other hand, are involved in response to environmental stresses or plant interactions with the others species and their environment. Despite ongoing research, there is still much to learn about how these molecules were involved in plant adaptation to land. Interaction between proteins is one of the key processes allowing cells to specify and regulate their development and their response to the environmental constraints. The study of interactions between proteins is then essential in the understanding of many biological mechanisms. In plants, the role of protein-protein interactions in many biological mechanisms is yet not clear. Particularly, the extend and role of interaction between proteins in different plant lineages is unknown limiting our understanding of important biological events such as plant adaptation to land.
The EPPIMAL project searched to give insights into the role of interactions between proteins in the context of plant evolution and adaptation to land. Specifically, it aims to understand how proteins in the phenylpropanoid and apo-carotenoid derived pathways interact with other proteins in different plant species. The project focuses on three plants that are distantly related but represent major evolutionary branches: the flowering plant Arabidopsis thaliana, the liverwort Marchantia polymorpha, and the moss Physcomitrium patens. By studying these species, we hope to better understand the evolution of phenylpropanoid and apo-carotenoid derived metabolic pathways and their influence in the mechanisms contributing to plant adaptation to land. Specifically, in the apo-carotenoid derived pathways, the project focusses on the study of the abscisic acid (ABA) a key molecule involved in response to environmental stresses and plant development.