Transcriptomic Profiling of Pep1-Induced Responses Under Phosphate Deficiency

In Arabidopsis thaliana, damage-inducible Pep peptides, perceived by the leucine rich repeat receptor kinases PEPR1/PEPR2, activate defense signaling and pathogen resistance. Here, we show that Pep1-induced defense responses are sensitized in phosphate (Pi)-deprived seedlings. This Pep-induced defense sensitization depends on root iron accumulation, facilitated by ferroxidases LPR1/LPR2 under Pi deficiency. Notably, PSR-related gene induction under Pi deficiency is diminished in non-elicited pepr1 pepr2 plants, revealing an unexpected role for Pi starvation responses beyond immunity.