An OPR3-independent pathway uses 4,5-didehydrojasmonate for jasmonate synthesis

OPR3 is required to reduce the JA-Ile precursor OPDA. Analyses of JA levels in a loss-of-function opr3-3 mutant identified an OPR3-independent pathway for JA-Ile biosynthesis, based on OPDA conversion to 4,5-ddh-JA and reduction to JA by OPR2.