GSE195837
Ligand diversity guarantees full activation of the jasmonate pathway in Marchantia polymorpha (RNA-Seq)
In plants, jasmonate signalling regulates a wide range of processes from growth and develop-ment to defence responses and thermotolerance. Bioactive jasmonates, such as JA, JA-Ile, OPDA and dn-OPDA, are derived from C18- and C16- fatty acids (FAs), which are found ubiquitously in the plant kingdom. Bryophytes also contain long chain C20- and C22- FAs (LCFAs), which are absent in most vascular plants but are found in organisms of other king-doms, including mammals. The existence of bioactive jasmonates derived from LCFAs is cur-rently unknown. Here, we describe the identification of an OPDA-like molecule derived from a C20-FA in Marchantia polymorpha, which we term C20-OPDA. This molecule accumulates upon wounding, and when applied exogenously can activate known COI1-dependent and -independent jasmonate responses. Furthermore, we identify a dn-OPDA-like molecule (?4-dn-OPDA) deriving from C20-OPDA and demonstrate it to be a ligand of the jasmonate co-receptor (MpCOI1-MpJAZ) in Marchantia. By analysing mutants involved in the production of LCFAs, we elucidate the major biosynthetic pathway of C20-OPDA and ?4-dn-OPDA. Moreover, using a double mutant compromised in the production of both ?4-dn-OPDA and dn-OPDA, we demonstrate the additive nature of these molecules in the activation of jasmonate responses. Taken together, our data identify LCFAs as a source of bioactive jasmonates that are essential to plant plasticity and resilience. Overall design: 3 replicates for mock and wound-treated samples