title: Barley MLA immune receptors directly interfere with antagonistically acting transcription factors to initiate disease resistance signaling.
abstract: The nucleotide binding domain and Leucine-rich repeat (NLR)-containing proteins in plants and animals mediate pathogen sensing inside host cells and mount innate immune responses against microbial pathogens. The barley (Hordeum vulgare) mildew A (MLA) locus encodes coiled-coil (CC)-type NLRs mediating disease resistance against the powdery mildew pathogen Blumeria graminis. Here, we report direct interactions between MLA and two antagonistically acting transcription factors, MYB6 and WRKY1. The N-terminal CC signaling domain of MLA interacts with MYB6 to stimulate its DNA binding activity. MYB6 functions as a positive regulator of basal and MLA-mediated immunity responses to B. graminis. MYB6 DNA binding is antagonized by direct association with WRKY1 repressor, which in turn also interacts with the MLA CC domain. The activated form of full-length MLA10 receptor is needed to release MYB6 activator from WRKY1 repression and to stimulate MYB6-dependent gene expression. This implies that, while sequestered by the WRKY1 repressor in the presence of the resting immune receptor, MYB6 acts as an immediate and positive postactivation signaling component of the active state of MLA during transcriptional reprogramming for innate immune responses.
authors.affiliation: State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Chang
authors.forename: Deshui
authors.initials: D
authors.lastname: Yu
authors.forename: Jian
authors.initials: J
authors.lastname: Jiao
authors.forename: Shaojuan
authors.initials: S
authors.lastname: Jing
authors.forename: Paul
authors.initials: P
authors.lastname: Schulze-Lefert
authors.forename: Qian-Hua
authors.initials: QH
authors.lastname: Shen
mesh_terms: D001203:Ascomycota / Q000276:immunology / Q000472:pathogenicity; D001483:Base Sequence; D060467:Disease Resistance; D018506:Gene Expression Regulation, Plant; D056426:Genetic Loci; D001467:Hordeum / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D057865:Plant Immunity; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D012045:Regulatory Sequences, Nucleic Acid; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors