Algal Remodeling in a Ubiquitous Planktonic Photosymbiosis
| Type | : | ACL |
|---|---|---|
| Nature | : | Production scientifique |
| Au bénéfice du Laboratoire | : | Oui |
| Statut de publication | : | Publié |
| Année de publication | : | 2019 |
| Auteurs (18) | : | DECELLE Johan STRYHANYUK Hryhoriy GALLET Benoit VERONESI Giulia SCHMIDT Matthias BALZANO Sergio MARRO Sophie UWIZEYE Clarisse JOUNEAU Pierre-henri LUPETTE Josselin JOUHET Juliette MARÉCHAL Eric SCHWAB Yannick SCHIEBER Nicole,l TUCOULOU Rémi RICHNOW Hans FINAZZI Giovanni MUSAT Niculina |
| Revue scientifique | : | Current Biology |
| Volume | : | 29 |
| Fascicule | : | 6 |
| Pages | : | 968-978 |
| DOI | : | 10.1016/j.cub.2019.01.073 |
| URL | : | http://www.sciencedirect.com/science/article/pii/s0960982219301320 |
| Abstract | : | Photosymbiosis between single-celled hosts and microalgae is common in oceanic plankton, especially in oligotrophic surface waters. However, the functioning of this ecologically important cell-cell interaction and the subcellular mechanisms allowing the host to accommodate and benefit from its microalgae remain enigmatic. Here, using a combination of quantitative single-cell structural and chemical imaging techniques (FIB-SEM, nanoSIMS, Synchrotron X-ray fluorescence), we show that the structural organization, physiology, and trophic status of the algal symbionts (the haptophyte Phaeocystis) significantly change within their acantharian hosts compared to their free-living phase in culture. In symbiosis, algal cell division is blocked, photosynthesis is enhanced, and cell volume is increased by up to 10-fold with a higher number of plastids (from 2 to up to 30) and thylakoid membranes. The multiplication of plastids can lead to a 38-fold increase of the total plastid volume in a cell. Subcellular mapping of nutrients (nitrogen and phosphorous) and their stoichiometric ratios shows that symbiotic algae are impoverished in phosphorous and suggests a higher investment in energy-acquisition machinery rather than in growth. Nanoscale imaging also showed that the host supplies a substantial amount of trace metals (e.g., iron and cobalt), which are stored in algal vacuoles at high concentrations (up to 660 ppm). Sulfur mapping reveals a high concentration in algal vacuoles that may be a source of antioxidant molecules. Overall, this study unveils an unprecedented morphological and metabolic transformation of microalgae following their integration into a host, and it suggests that this widespread symbiosis is a farming strategy wherein the host engulfs and exploits microalgae. |
| Mots-clés | : | symbiosis; plankton; microalga; single-cell imaging; photosynthesis; mass spectrometry imaging; 3D electron microscopy; eukaryotes; plastid; Phaeocystis |
| Commentaire | : | - |
| Tags | : | - |
| Fichier attaché | : | - |
| Citation | : |
Decelle J, Stryhanyuk H, Gallet B, Veronesi G, Schmidt M, Balzano S, Marro S, Uwizeye C, Jouneau P-H, Lupette J, Jouhet J, Maréchal E, Schwab Y, Schieber NL, Tucoulou R, Richnow H, Finazzi G, Musat N (2019) Algal Remodeling in a Ubiquitous Planktonic Photosymbiosis. Curr Biol 29: 968-978 | doi: 10.1016/j.cub.2019.01.073
|