Guillaume Gilliard, Jelena Pršić, Jean‐Marc Crowet, Catherine Chemotti, Jahed Ahmed, Joseph H. Lorent, Marie-Dominique Jolivet, Sabrina Egli, Stéphane Égée, Guillaume Bouyer, Gaëlle Race, Lennard van Buren, Anke Van Den Berghe, Anthony Argüelles-Arias, Marion Mathelié‐Guinlet, Heba Ibrahim, Manon Genva, Laëtitia Fouillen, Cécile Mirande-Bret, Oihana Razin, Brian Vue, Milan Župunski, W. Patricio Luzuriaga-Loaiza, Estelle Deboever, M.Nail Nasir, Laurence Lins, Patrick Van Deŕ Smissen, Farah Boubsi, Sabine Eschrig, Véronique Germain, Monica Höfte, Cyril Zipfel, Yves F. Dufrêne, Donatienne Tyteca, Alexandros Koutsioubas, Paola Brocca, Guido Grossman, Stefanie Ranf, Stéphan Dorey, Barbara De Coninck, Thorsten Nürnberger, Sébastien Mongrand, Julien Gronnier, Valeria Rondelli, Magali Deleu, Marc Ongena
Bacteria-derived lipopeptides are immunogenic triggers of host defences in metazoans and plants. Root-associated rhizobacteria produce cyclic lipopeptides that activate induced systemic resistance against microbial infection in various plant species. Whether and how these molecules are perceived at the plant cell surface remains elusive. Here we reveal that immune activation in Arabidopsis thaliana by the lipopeptide elicitor surfactin is mediated via a specific interaction with membrane sphingolipids. It relies on host membrane remodelling and subsequent activation of mechanosensitive ion channels. This mechanism leads to host defence potentiation and resistance to the necrotrophic fungus Botrytis cinerea and appears distinct from pattern-triggered immunity induced by classical host pattern recognition receptors. These results reveal a previously uncharacterized mechanism through which lipopeptides derived from non-pathogenic bacteria activate plant immune responses. This work unveils a non-canonical lipid-driven mechanism for plant immune activation by a bacterial lipopeptide. Perception at the cell membrane leads to deformation, mechanosensing and early signalling and culminates in systemic resistance priming.