Transcriptome responses to perturbed SA levels in dmr6/dlo1 mutants and DMR6/DLO1 overexpression lines in Arabidopsis thaliana

The hormone salicylic acid (SA) plays a crucial role in plant immunity by activating responses that arrest pathogen ingress. Since SA accumulation also penalizes growth, the question remains why unchallenged, healthy plants synthesize this hormone. By overexpressing SA-inactivating hydroxylases in Arabidopsis we reveal that basal SA levels are needed to have appropriate expression of selected immune receptor and signaling genes, thus enabling early pathogen detection and immune responses.