Open AccessBacterial rhamnolipids and their 3-hydroxyalkanoate precursors activate Arabidopsis innate immunity through two independent mechanisms
Author(s) -
Romain Schellenberger,
Jérôme Crouzet,
Arvin Nickzad,
LinJie Shu,
Alexander Kutschera,
Tim Gerster,
Nicolas Borie,
Corinna Dawid,
Maude Cloutier,
Sandra Villaume,
Sandrine DhondtCordelier,
Jane Hubert,
Sylvain Cordelier,
Florence Mazeyrat-Gourbeyre,
Christian Schmid,
Marc Ongena,
JeanHugues Renault,
Arnaud Haudrechy,
Thomas Hofmann,
Fabienne Baillieul,
Christophe Clément,
Cyril Zipfel,
Charles Gauthier,
Éric Déziel,
Stefanie Ranf,
Stéphan Dorey
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2101366118
Subject(s) - biology , arabidopsis , innate immune system , pseudomonas syringae , microbiology and biotechnology , plant immunity , immune system , burkholderia cenocepacia , rhamnose , arabidopsis thaliana , pattern recognition receptor , acquired immune system , immunity , burkholderia , pathogen , bacteria , biochemistry , gene , immunology , genetics , mutant , galactose
Plant innate immunity is activated upon perception of invasion pattern molecules by plant cell-surface immune receptors. Several bacteria of the genera Pseudomonas and Burkholderia produce rhamnolipids (RLs) from l-rhamnose and ( R )-3-hydroxyalkanoate precursors (HAAs). RL and HAA secretion is required to modulate bacterial surface motility, biofilm development, and thus successful colonization of hosts. Here, we show that the lipidic secretome from the opportunistic pathogen Pseudomonas aeruginosa , mainly comprising RLs and HAAs, stimulates Arabidopsis immunity. We demonstrate that HAAs are sensed by the bulb-type lectin receptor kinase LIPOOLIGOSACCHARIDE-SPECIFIC REDUCED ELICITATION/S-DOMAIN-1-29 (LORE/SD1-29), which also mediates medium-chain 3-hydroxy fatty acid (mc-3-OH-FA) perception, in the plant Arabidopsis thaliana HAA sensing induces canonical immune signaling and local resistance to plant pathogenic Pseudomonas infection. By contrast, RLs trigger an atypical immune response and resistance to Pseudomonas infection independent of LORE. Thus, the glycosyl moieties of RLs, although abolishing sensing by LORE, do not impair their ability to trigger plant defense. Moreover, our results show that the immune response triggered by RLs is affected by the sphingolipid composition of the plasma membrane. In conclusion, RLs and their precursors released by bacteria can both be perceived by plants but through distinct mechanisms.