Abstract
Plants suffer from various types of oxidative stress in their life cycles. It is derived from both biotic and abiotic reasons, such as ozone exposure, wounding, high light, and various diseases. Jasmonic acid (JA) and methyl jasmonate (MeJA) are known as important signals in the oxidative stresses. Recent reports suggest that a cyclopentenone precursor of JAs (JA and MeJA), 12-oxo-phytodienoic acid (OPDA) itself induces gene expression like as JAs. However, little is known about physiological significance of the OPDA-dependent gene expression. We globally compared JA-, MeJA-, and OPDA-responsive genes and revealed a presence of OPDA-specific response genes in Arabidopsis. Analysis using mutants deficient in the biosynthesis of JAs revealed that OPDA functions as a signaling molecule in wounding response. Unlike signaling via JAs, OPDA signaling is COI1-independent. These results indicate that two types of oxylipins, OPDA and JAs differently function in wounding response in Arabidopsis.
