Abstract
Sterols and triterpenes are industrially so important that they are used as herbal medicines and as row materials of various therapeutic steroids. Currently, shortage of natural resources and risk of pathogen contamination in animal-oriented resources prompted us to establish new processes for sterol-production using row materials of plant origin. In plants, responsible genes for more than 30 enzymatic steps in the sterol-biosynthesis pathway were assigned, while their regulation at both transcriptional and translational levels are still obscure. Furthermore, almost nothing is known about how sterols are transported and stored in plant cells. Practical process to produce desirable sterols using plant will not be fully established until these unknown factors are clarified. Recent advances in the study of sterol homeostasis in other kingdom, like fungus and animal, will be reviewed. Insights obtained through this comparative study would be helpful to elucidate sterol metabolism in plant.
