title: Salicylic acid regulates Arabidopsis microbial pattern receptor kinase levels and signaling.
abstract: In Arabidopsis thaliana, responses to pathogen-associated molecular patterns (PAMPs) are mediated by cell surface pattern recognition receptors (PRRs) and include the accumulation of reactive oxygen species, callose deposition in the cell wall, and the generation of the signal molecule salicylic acid (SA). SA acts in a positive feedback loop with ACCELERATED CELL DEATH6 (ACD6), a membrane protein that contributes to immunity. This work shows that PRRs associate with and are part of the ACD6/SA feedback loop. ACD6 positively regulates the abundance of several PRRs and affects the responsiveness of plants to two PAMPs. SA accumulation also causes increased levels of PRRs and potentiates the responsiveness of plants to PAMPs. Finally, SA induces PRR- and ACD6-dependent signaling to induce callose deposition independent of the presence of PAMPs. This PAMP-independent effect of SA causes a transient reduction of PRRs and ACD6-dependent reduced responsiveness to PAMPs. Thus, SA has a dynamic effect on the regulation and function of PRRs. Within a few hours, SA signaling promotes defenses and downregulates PRRs, whereas later (within 24 to 48 h) SA signaling upregulates PRRs, and plants are rendered more responsive to PAMPs. These results implicate multiple modes of signaling for PRRs in response to PAMPs and SA.
authors.affiliation: Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637.
authors.forename: Chika
authors.initials: C
authors.lastname: Tateda
authors.affiliation: Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637.
authors.forename: Zhongqin
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637.
authors.forename: Jay
authors.initials: J
authors.lastname: Shrestha
authors.affiliation: Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637.
authors.forename: Joanna
authors.initials: J
authors.lastname: Jelenska
authors.affiliation: Zurich-Basel Plant Science Center, Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland.
authors.forename: Delphine
authors.initials: D
authors.lastname: Chinchilla
authors.affiliation: Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637 jgreenbe@uchicago.edu.
authors.forename: Jean T
authors.initials: JT
authors.lastname: Greenberg
mesh_terms: D017487:Ankyrins / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005408:Flagellin / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D005936:Glucans / Q000378:metabolism; D054884:Host-Pathogen Interactions; D015151:Immunoblotting; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D011485:Protein Binding / Q000187:drug effects; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D044224:Pseudomonas syringae / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D051192:Receptors, Pattern Recognition / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020156:Salicylic Acid / Q000819:agonists / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D013830:Thiadiazoles / Q000494:pharmacology
chemical_list: C480953:ACD6 protein, Arabidopsis; D017487:Ankyrins; D029681:Arabidopsis Proteins; D005936:Glucans; D017382:Reactive Oxygen Species; D051192:Receptors, Pattern Recognition; D013830:Thiadiazoles; D005408:Flagellin; C048306:callose; C099403:S-methyl benzo(1,2,3)thiadiazole-7-carbothioate; D011494:Protein Kinases; C463660:BAK1 protein, Arabidopsis; C411853:FLS2 protein, Arabidopsis; C525882:CERK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D020928:Mitogen-Activated Protein Kinases; D020156:Salicylic Acid