Carotenoid cleavage dioxygenase genes from fruit

The oxidative cleavage of carotenoids and xanthophylls yields apocarotenoids and is catalyzed by a family of carotenoid cleavage dioxygenases (CCDs). Numerous CCDs have been cloned and functionally characterized since the discovery of the first carotenase gene VP14 in 1997. In plants, CCDs are expressed in different tissues such as roots, shoots, leaves, flowers and fruits where they are implicated in various processes including plant growth regulation, plant hormone formation and production of volatiles. Since apocarotenals are important secondary metabolites that contribute to the quality of fresh fruit homologs of CCD genes have been identified in tomato, grape, apple, mandarin, orange, lemon, melon, peach and strawberry. Here, CCDs are discussed according to their roles in fruit.