Mutants of Arabidopsis reveal many roles for membrane lipids.

Polyunsaturated acyl lipids constitute approximately 50% of the hydrophobic membrane barriers that delineate the compartments of cells. The composition of these lipids is critically important for many membrane functions and, thus, for proper growth and development of all living organisms. In the model plant Arabidopsis, the isolation of mutants with altered lipid compositions has facilitated biochemical and molecular approaches to understanding lipid metabolism and membrane biogenesis. Just as importantly, the availability of a series of plant lines with specific changes in membrane lipids have provided a new resource to study the structural and adaptive roles of lipids. Now, the sequencing of the Arabidopsis genome, and the development of reverse-genetics approaches provide the tools needed to make additional discoveries about the relationships between lipid structure and membrane function in plant cells.