Plant oxylipins: Plant responses to 12‐oxo‐phytodienoic acid are governed by its specific structural and functional properties

Abstract

One of the most challenging questions in modern plant science is how plants regulate their morphological and developmental adaptation in response to changes in their biotic and abiotic environment. A comprehensive elucidation of the underlying mechanisms will help shed light on the extremely efficient strategies of plants in terms of survival and propagation. In recent years, a number of environmental stress conditions have been described as being mediated by signaling molecules of the oxylipin family. In this context, jasmonic acid, its biosynthetic precursor, 12‐oxo‐phytodienoic acid (OPDA), and also reactive electrophilic species such as phytoprostanes play pivotal roles. Although our understanding of jasmonic acid‐dependent processes and jasmonic acid signal‐transduction cascades has made considerable progress in recent years, knowledge of the regulation and mode of action of OPDA‐dependent plant responses is just emerging. This minireview focuses on recent work concerned with the elucidation of OPDA‐specific processes in plants. In this context, aspects such as the differential recruitment of OPDA, either by de novo biosynthesis or by release from cyclo‐oxylipin‐galactolipids, and the conjugation of free OPDA are discussed.

12-oxo-phytodienoic acid interaction with cyclophilin CYP20-3 is a benchmark for understanding retrograde signaling in plants

“…The mediator of such OPDA retrograde signaling, however, seems to be not the cysteine per se but a change in redox potential caused by increased concentration of thiol groups. Increased cysteine synthesis leads to synthesis of glutathione that can convey the redox signal to the TGA transcription factors, which have been shown previously to be redox-sensitive (19). Thus, sulfur metabolites are necessary for the OPDA-triggered retrograde signaling.…”

Maize death acids, 9-lipoxygenase–derived cyclopente(a)nones, display activity as cytotoxic phytoalexins and transcriptional mediators

“…Genetic evidence in maize (Zea mays) supports a role for JA biosynthesis in the survival of biotic stress, regulation of senescence, and cell death processes mediating male sex determination (8,9). As a precursor, 12-OPDA can trigger developmental processes and defense signaling different from JA-Ile (10)(11)(12). During physiological stress, 12-OPDA binds cyclophilin 20-3 which facilitates recruitment of a cysteine synthase complex…”

Proteomic analysis ofPhyscomitrella patenstreated with 12-oxo-phytodienoic acid, an important oxylipin in plants

“…1) A transcriptome analysis in Arabidopsis showed that many genes were induced by OPDA, but not by JA.…”