Plant desaturases: harvesting the fat of the land.

The past few years have witnessed a major upsurge in research towards the goal of modifying the lipid composition of plants. Genes encoding a range of different fatty acid desaturase activities have been cloned, and the evolutionary relationships between and within different classes of enzymes have tentatively been established. The effects of expressing some of these desaturases in heterologous hosts have also been studied, often producing unexpected results which contribute further to our understanding of plant lipid modification. It is to be hoped that, in the near future, the goal of producing unusual and valuable fatty acids in transgenic oilseeds will be achieved on a commercial scale.