Abstract
Jasmonic acid (JA) is known to be an important signaling molecule in defense responses against pathogen attack. JA is synthesized in the octadecanoid pathway, which employs several enzymes including allene oxide cyclase (AOC) and 12-oxo-phytodienoic acid (OPDA) reductase (OPR). Recent studies in Arabidopsis suggest that OPDA, an intermediate in the biosynthesis of JA, is also involved in defense responses. However, little is known about physiological roles of OPDA in defense responses in rice. We generated transgenic rice plants in which the expression of the genes encoding AOC and OPR (OsAOC, OsOPR1 and OsOPR3) is suppressed by RNAi method. JA content was undetectable in leaves of the OsAOC-suppressed transformant, and was reduced by approximately 3% in leaves of the OsOPR1-OsOPR3-co-suppressed transformant. We will also report the OPDA content in the OsAOC-suppressed rice.
