Plant sphingolipids today - Are they still enigmatic?

Sphingolipids are a diverse group of lipids found in all eukaryotes and some bacteria, consisting of a hydrophobic ceramide and a hydrophilic head group. We have summarised the contemporary understanding of the structure of plant sphingolipids with an emphasis on glucosylceramides and inositolphosphorylceramides. Plant glucosylceramides are important structural components of plasma and vacuole membranes. inositolphosphorylceramides have been identified as moieties of the glycosylphosphorylinositol (GPI) anchors of plant proteins targeted to the plasma membrane. in the last few years, progress has been made in the cloning of plant genes coding for enzymes involved in sphingolipid metabolism. As found in yeast and mammals, the plant sphingolipid pathway is a potential generator of powerful cell signals. The role of plant sphingolipid metabolites in programmed cell death and calcium influx is discussed