Decoding Arabidopsis growth-defense trade-offs through ADR1-associated transcriptional networks

Growth and defense are inversely correlated processes requiring balance for fitness. While each is well studied, its regulatory trade-offs are less understood. Using DANGEROUS MIX (DM) autoimmune plants with stunted growth in Arabidopsis thaliana, we investigate the balancing act. Transcriptome analysis of three DM cases and pathogen-treated seedlings identifies two major modules representing defense and growth. These core modules, comprising 4,712 genes (∼17% of the transcriptome), reveal consistent transcriptional antagonism across diverse immune datasets. Removing all three ADR1s, the helper nucleotide-binding leucine-rich repeats (NLRs), reverses the expression patterns of both modules and shifts the balance; ADR1s strongly affect growth-associated receptor-like kinase (RLK) genes more than defense genes. Autoimmune plants also show reciprocal chromatin accessibility changes, dominated by a widespread decrease at growth loci relative to sporadic increases at defense loci. Our findings suggest a mechanism where immune signaling, partly mediated by ADR1s, actively suppresses growth genes, providing a strategy to regulate the growth-defense trade-off.