Molecular insights into the Darwin paradox of coral reefs from the sea anemone Aiptasia.

Cui, Guoxin; Konciute, Migle K; Ling, Lorraine; Esau, Luke; Raina, Jean-Baptiste; Han, Baoda; Salazar, Octavio R; Presnell, Jason S; Radecker, Nils; Zhong, Huawen; Menzies, Jessica; Cleves, Phillip A; Liew, Yi Jin; Krediet, Cory J; Sawiccy, Val; Cziesielski, Maha J; Guagliardo, Paul; Bougoure, Jeremy; Pernice, Mathieu; Hirt, Heribert; Voolstra, Christian R; Weis, Virginia M; Pringle, John R; Aranda, Manuel
2023
Science advances
DOI
10.1126/sciadv.adf7108
Symbiotic cnidarians such as corals and anemones form highly productive and biodiverse coral reef ecosystems in nutrient-poor ocean environments, a phenomenon known as Darwin's paradox. Resolving this paradox requires elucidating the molecular bases of efficient nutrient distribution and recycling in the cnidarian-dinoflagellate symbiosis. Using the sea anemone Aiptasia, we show that during symbiosis, the increased availability of glucose and the presence of the algae jointly induce the coordinated up-regulation and relocalization of glucose and ammonium transporters. These molecular responses are critical to support symbiont functioning and organism-wide nitrogen assimilation through glutamine synthetase/glutamate synthase-mediated amino acid biosynthesis. Our results reveal crucial aspects of the molecular mechanisms underlying nitrogen conservation and recycling in these organisms that allow them to thrive in the nitrogen-poor ocean environments.