Subjects: Molecular biology, Signaling Cascades, Research Article, Transcription Factors, Regulatory Proteins, Genetics, Leaves, Flowering Plants, Stress Signaling Cascade, Plants, Molecular biology techniques, Proteins, Plant Science, Experimental Organism Systems, Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy), Sequencing techniques, DNA-binding proteins, Biology and Life Sciences, Signal Transduction, Research and analysis methods, Plant Anatomy, Medicinsk bioteknologi (med inriktning mot cellbiologi (inklusive stamcellsbiologi), molekylärbiologi, mikrobiologi, biokemi eller biofarmaci), Medicine, Plant and Algal Models, RNA sequencing, Q, R, Cell Biology, Phenotypes, Model Organisms, Gene Regulation, Cell Signaling, Biochemistry, Science, Organisms, Brassica, Arabidopsis Thaliana, Gene Expression
The conserved protein complex known as Mediator conveys transcriptional signals by acting as an intermediary between transcription factors and RNA polymerase II. As a result, Mediator subunits play multiple roles in regulating developmental as well as abiotic and biotic stress pathways. In this report we identify the head domain subunits MEDIATOR18 and MEDIATOR20 as important susceptibility factors for Fusarium oxysporum infection in Arabidopsis thaliana. Mutants of MED18 and MED20 display down-regulation of genes associated with jasmonate signaling and biosynthesis while up-regulation of salicylic acid associated pathogenesis related genes and reactive oxygen producing and scavenging genes. We propose that MED18 and MED20 form a sub-domain within Mediator that controls the balance of salicylic acid and jasmonate associated defense pathways.