title: A Suite of Receptor-Like Kinases and a Putative Mechano-Sensitive Channel Are Involved in Autoimmunity and Plasma Membrane-Based Defenses in Arabidopsis.
abstract: In plants, cell surface pattern recognition receptors (PRRs) provide a first line of defense against pathogens. Although each PRR recognizes a specific ligand, they share common signaling outputs, such as callose and other cell wall-based defenses. Several PRRs are also important for callose induction in response to the defense signal salicylic acid (SA). The extent to which common components are needed for PRR signaling outputs is not known. The gain-of-function Arabidopsis mutant of ACCELERATED CELL DEATH6 (ACD6) acd6-1 shows constitutive callose production that partially depends on PRRs. ACD6-1 (and ACD6) forms complexes with the PRR FLAGELLIN SENSING2, and ACD6 is needed for responses to several PRR ligands. Thus, ACD6-1 could serve as a probe to identify additional proteins important for PRR-mediated signaling. Candidate signaling proteins (CSPs), identified in our proteomic screen after immunoprecipitation of hemagglutinin (HA)-tagged ACD6-1, include several subfamilies of receptor-like kinase (RLK) proteins and a MECHANO-SENSITIVE CHANNEL OF SMALL CONDUCTANCE-LIKE 4 (MSL4). In acd6-1, CSPs contribute to autoimmunity. In wild type, CSPs are needed for defense against bacteria and callose responses to two or more microbial-derived patterns and an SA agonist. CSPs may function to either i) promote the assembly of signaling complexes, ii) regulate the output of known PRRs, or both.
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Zhongqin
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Chika
authors.initials: C
authors.lastname: Tateda
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Shang-Chuan
authors.initials: SC
authors.lastname: Jiang
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Jay
authors.initials: J
authors.lastname: Shrestha
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Joanna
authors.initials: J
authors.lastname: Jelenska
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: DeQuantarius J
authors.initials: DJ
authors.lastname: Speed
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago.
authors.forename: Jean T
authors.initials: JT
authors.lastname: Greenberg
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000378:metabolism*; D015551:Autoimmunity; D002462:Cell Membrane / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D040542:Mechanotransduction, Cellular; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D044224:Pseudomonas syringae / Q000254:growth & development; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D015854:Up-Regulation / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D012333:RNA, Messenger; D017346:Protein Serine-Threonine Kinases; D020156:Salicylic Acid