Progress and Prospects of Research on the Role of Phosphatidic Acid in Response to Adverse Stress in Plants

Lipid signaling plays a crucial role in how plants perceive and respond to environmental challenges. Among the various lipid mediators, phosphatidic acid (PA) serves as a key metabolic intermediate and second messenger that links membrane dynamics with stress signaling. It is produced rapidly through the coordinated actions of phospholipase C, phospholipase D and diacylglycerol kinase, and its transient accumulation enables plants to adjust defense and acclimation responses with remarkable precision. Recent studies have shown that PA participates in immune signaling, osmotic regulation, and redox control, functioning at the intersection of membrane remodeling and intracellular signal transduction. Through interactions with hormone signaling, calcium fluxes, and reactive oxygen species production, PA integrates multiple stress-responsive pathways, thereby helping to maintain physiological homeostasis under adverse conditions. This review summarizes current understanding of the biosynthetic regulation and signaling roles of PA, and discusses emerging perspectives that highlight its central role in plant immunity and stress adaptation.