Carotenoid metabolic engineering in flowering plants.

In plants, color is a powerful tool to attract insects and herbivores which act as pollinators and vehicles of seed dispersion. In particular, flower color has held key post for human with aesthetic value. Horticultural industry has developed methods to produce new and attractive color varieties in flowering plants. Carotenoids are one of the main pigments being responsible for red, orange, and yellow colors. Their biosynthetic pathway has been considered as a major target of metabolic engineering for color modification of flowers and fruits. Here, we review the diverse efforts to modify pigment phenotype by the control of carotenogenic gene expression and enzyme levels. Recent reports about regulating degradation and storage of carotenoids will be also summarized to help the creation of engineered flower with novel color phenotype which is not existed in nature.