Sphingolipids in plant abiotic stress responses

Sphingolipids are essential structural components of biological membranes and signaling molecules that orchestrate plant growth, development, and responses to biotic and abiotic stresses. Sphingolipid signaling pathways exhibit extensive crosstalk with hormone and stress-signaling pathways. Here, we review plant sphingolipid metabolism, including the key nodes and rate-limiting steps, and examine the roles of sphingolipids in plant responses to abiotic stresses. For example, long-chain base-1-phosphates function in abscisic acid-mediated closure of stomata during drought. In addition, glycosyl inositol phosphoceramides act as sodium ion sensors, integrating ionic and osmotic signals in calcium-mediated cascades. Furthermore, sphingolipids and their derivatives participate in processes such as alterations in membrane properties, programmed cell death, autophagy, and production of reactive oxygen species. Elucidating the details of these processes and networks is vital for developing crops with enhanced resilience to stressful environmental conditions. In this review, we synthesize current knowledge on how distinct sphingolipid species and their metabolic and signaling pathways regulate plant responses to major abiotic stresses, focusing on drought, temperature extremes, hypoxia, and oxidative stress.