title: LYM2-dependent chitin perception limits molecular flux via plasmodesmata.
abstract: Chitin acts as a pathogen-associated molecular pattern from fungal pathogens whose perception triggers a range of defense responses. We show that LYSIN MOTIF DOMAIN-CONTAINING GLYCOSYLPHOSPHATIDYLINOSITOL-ANCHORED PROTEIN 2 (LYM2), the Arabidopsis homolog of a rice chitin receptor-like protein, mediates a reduction in molecular flux via plasmodesmata in the presence of chitin. For this response, lym2-1 mutants are insensitive to the presence of chitin, but not to the flagellin derivative flg22. Surprisingly, the chitin-recognition receptor CHITIN ELCITOR RECEPTOR KINASE 1 (CERK1) is not required for chitin-induced changes to plasmodesmata flux, suggesting that there are at least two chitin-activated response pathways in Arabidopsis and that LYM2 is not required for CERK1-mediated chitin-triggered defense responses, indicating that these pathways are independent. In accordance with a role in the regulation of intercellular flux, LYM2 is resident at the plasma membrane and is enriched at plasmodesmata. Chitin-triggered regulation of molecular flux between cells is required for defense responses against the fungal pathogen Botrytis cinerea, and thus we conclude that the regulation of symplastic continuity and molecular flux between cells is a vital component of chitin-triggered immunity in Arabidopsis.
authors.affiliation: John Innes Centre and The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, United Kingdom. c.faulkner@brookes.ac.uk
authors.forename: Christine
authors.initials: C
authors.lastname: Faulkner
authors.forename: Elena
authors.initials: E
authors.lastname: Petutschnig
authors.forename: Yoselin
authors.initials: Y
authors.lastname: Benitez-Alfonso
authors.forename: Martina
authors.initials: M
authors.lastname: Beck
authors.forename: Silke
authors.initials: S
authors.lastname: Robatzek
authors.forename: Volker
authors.initials: V
authors.lastname: Lipka
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Maule
mesh_terms: D000814:Aniline Compounds; D017360:Arabidopsis; D029681:Arabidopsis Proteins / Q000378:metabolism*; D020171:Botrytis; D002450:Cell Communication / Q000276:immunology*; D002686:Chitin / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D018613:Microscopy, Confocal; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D030821:Plants, Genetically Modified; D031425:Plasmodesmata / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D016897:Respiratory Burst / Q000502:physiology; D014343:Trypan Blue
chemical_list: D000814:Aniline Compounds; D029681:Arabidopsis Proteins; C580621:LYM2 protein, Arabidopsis; D017382:Reactive Oxygen Species; D011956:Receptors, Cell Surface; D002686:Chitin; C017006:aniline blue; C525882:CERK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D014343:Trypan Blue
keywords: PAMP-triggered immunity; cell-to-cell communication