Diversity in sphingolipid metabolism across land plants

Sphingolipid profiles vary substantially across terrestrial plant lineages. This review describes those of several model systems, and what we can infer about sphingolipid biosynthesis and physiological function from this metabolic diversity. Sphingolipids are essential metabolites found in all plant species. They are required for plasma membrane integrity, tolerance of and responses to biotic and abiotic stresses, and intracellular signalling. There is extensive diversity in the sphingolipid content of different plant species, and in the identities and roles of enzymes required for their processing. In this review, we survey results obtained from investigations of the classical genetic model Arabidopsis thaliana, from assorted dicots with less extensive genetic toolkits, from the model monocot Oryza sativa, and finally from the model bryophyte Physcomitrium patens. For each species or group, we first broadly summarize what is known about sphingolipid content. We then discuss the most insightful and puzzling features of modifications to the hydrophobic ceramides, and to the polar headgroups of complex sphingolipids. Altogether, these data can serve as a framework for our knowledge of sphingolipid metabolism across the plant kingdom. This chemical and metabolic heterogeneity underpins equally diverse functions. With greater availability of different tools for analytical measurements and genetic manipulation, our field is entering an exciting phase of expanding our knowledge of the biological functions of this persistently cryptic class of lipids.

Automated summary

This review discusses the diversity of sphingolipid profiles in different plant lineages and how they contribute to metabolic diversity and physiological functions. Sphingolipids are essential for various cellular processes in plants and their content varies across different species. The review focuses on model systems such as Arabidopsis thaliana, Oryza sativa, and Physcomitrium patens, summarizing the known sphingolipid content and discussing modifications to hydrophobic ceramides and polar headgroups. This knowledge serves as a framework for understanding sphingolipid metabolism in plants.