Influence of Lysophosphatidylethanolamine on Reactive Oxygen Species, Ethylene Biosynthesis, and Auxin Action in Plant Tissue

Despite several approved uses of lysophosphatidylethanolamine (LPE) in agriculture, the mode of action in which LPE benefits plants is not clear. To understand LPE action, we first examined the effects of LPE treatment on reactive oxygen species (ROS) production in plant protoplast, since it has been suggested that intracellular ROS production is associated with the regulation of biosynthesis pathway of plant hormones such as auxin and ethylene. Our result revealed that LPE treatment increases the ROS production in plant cells, suggesting the possibility that LPE may modulate the hormone production in a ROS-mediated manner. In addition, monitoring of gene expression involved in ethylene biosynthesis showed that VR-ACS1 and VR-ACS7 genes expression were elevated by LPE treatment in mung bean hypocotyl segments. It indicates that LPE is closely involved in the induction of ethylene biosynthesis. Based on the bioassay results using auxin and the known interaction between auxin and ethylene, it is suggested that LPE action is entangled with auxin, ethylene, and auxin- and ethylene-dependent pathways.