Analysis using the Arabidopsis 9-LOX deletion mutant LOX1/LOX5 and the oxylipin-insensitive mutant nonresponding to oxylipins (noxy)2-2 and related mutants of brassinosteroids (BRs) showed that oxylipin from 9-LOX induces BR synthesis and signal transduction and activates cell wall responses, such as callus deposition, to limit pathogen invasion and prevent pathogen infection [37]. This evidence concerns the gene OLR1 and infection.