title: Waterborne signaling primes the expression of elicitor-induced genes and buffers the oxidative responses in the brown alga Laminaria digitata.
abstract: As marine sessile organisms, seaweeds must respond efficiently to biotic and abiotic challenges in their natural environment to reduce the fitness consequences of wounds and oxidative stress. This study explores the early steps of the defense responses of a large marine brown alga (the tangle kelp Laminaria digitata) and investigates its ability to transmit a warning message to neighboring conspecifics. We compared the early responses to elicitation with oligoguluronates in laboratory-grown and harvested wild individuals of L. digitata. We followed the release of H₂O₂ and the concomitant production of volatile organic compounds. We also monitored the kinetics of expression of defense-related genes following the oxidative burst. Laboratory-grown algae were transplanted in kelp habitats to further evaluate their responses to elicitation after a transient immersion in natural seawater. In addition, a novel conditioning procedure was established to mimic field conditions in the laboratory. Our experiments showed that L. digitata integrates waterborne cues present in the kelp bed and/or released from elicited neighboring plants. Indeed, the exposure to elicited conspecifics changes the patterns of oxidative burst and volatile emissions and potentiates this kelp for faster induction of genes specifically regulated in response to oligoguluronates. Thus, waterborne signals shape the elicitor-induced responses of kelps through a yet unknown mechanism reminiscent of priming in land plants.
authors: Marine Plants and Biomolecules Laboratory, Unité Mixte de Recherche 7139, Station Biologique de Roscoff, Université Pierre et Marie Curie, Roscoff, France.
authors: François
authors: F
authors: Thomas
authors: Audrey
authors: A
authors: Cosse
authors: Sophie
authors: S
authors: Goulitquer
authors: Stefan
authors: S
authors: Raimund
authors: Pascal
authors: P
authors: Morin
authors: Myriam
authors: M
authors: Valero
authors: Catherine
authors: C
authors: Leblanc
authors: Philippe
authors: P
authors: Potin
mesh_terms: D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects*; D006603:Hexuronic Acids / Q000494:pharmacology*; D007795:Laminaria / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016897:Respiratory Burst / Q000187:drug effects / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects* / Q000235:genetics; D013997:Time Factors; D055549:Volatile Organic Compounds / Q000378:metabolism; D014867:Water / Q000378:metabolism*
chemical_list: D006603:Hexuronic Acids; D012333:RNA, Messenger; D055549:Volatile Organic Compounds; D014867:Water; C007896:guluronic acid