CLONING AND EXPRESSION OF CYTOCHROME-P450 GENES-CONTROLLING FLOWER COLOR

BLUE and violet flowers generally contain derivatives of delphinidin; red and pink flowers generally contain derivatives of cyanidin or pela rgonidin1. Differences in hydroxylation patterns of these three major classes of anthocyanidins are controlled by the cytochrome P450 enzyme s flavonoid 3'-hydroxylase and flavonoid 3',5'-hydroxylase. Here we re port on the isolation of complementary DNA clones of two different fla vonoid 3',5'-hydroxylase genes that are expressed in petunia flowers. Restriction-fragment length polymorphism mapping and complementation o f mutant petunia lines showed that the flavonoid 3',5'-hydroxylase gen es correspond to the genetic loci Hf1 and Hf2.