A regulatory module controls plant growth and stress response by modulating hormone level

Perception and relay of cell wall signals is critical for plants to regulate growth and stress responses, but the mechanism underlying this biological process remains largely unknown. Here we report that RAPID ALKALINIZATION FACTOR (RALFs) peptides, Leucine-rich repeat extensins (LRXs) and FERONIA (FER) are physically associated in extracellular region. lrx345, fer-4, and transgenic plants overexpressing RALF22 or RALF23 all showed retarded growth, increased sensitivity to salt stress, and constitutively increased levels of ABA, JA, and SA. Salt treatment or chemical disruption of cell wall promotes the release of mature RALF peptides, which negatively regulate the function of FER by inducing its internalization. JA mutants coi1 and aos restore the retarded growth, and mutation of ABA2 suppresses the salt-sensitive phenotype of lrx345. Together, we propose that LRXs, RALFs, and FER function as a module to sense and transduce cell wall signals, thereby regulating growth and stress responses via hormones-mediated pathways. Overall design: RNA-Seq of 4 samples, each has 3 replicates. The samples are wild type ( WT ) and lrx345 before and after NaCl treatment.