The regulation of carotenoid pigmentation in flowers

Carotenoids fulfill many processes that are essential for normal growth and development in plants, but they are also responsible for the breathtaking variety of red-to-yellow colors we see in flowers and fruits. Although such visual diversity helps to attract pollinators and encourages herbivores to distribute seeds, humans also benefit from the aesthetic properties of flowers and an entire floriculture industry has developed on the basis that new and attractive varieties can be produced. Over the last decade, much has been learned about the impact of carotenoid metabolism on flower color development and the molecular basis of flower color. A number of different regulatory mechanisms have been described ranging from the transcriptional regulation of genes involved in carotenoid synthesis to the control of carotenoid storage in sink organs. This means we can now explain many of the natural colorful varieties we see around us and also engineer plants to produce flowers with novel and exciting varieties that are not provided by nature.

Research highlights
► Carotenoids are responsible for the variety of red-to-yellow colors in flowers.
► Biosynthesis can be controlled by transcriptional/post-transcriptional regulation.
► Lipoprotein-sequestering structures can act as carotenoid sinks.
► The accumulation of carotenoids can also be regulated by carotenoid degradation.
► Flower color can be controlled by the genetic modulation of carotenoid metabolism.